Physics Past Questions v23 for (JAMB/WAEC/NECO)

Physics Past Questions v23 For (JAMB/WAEC/NECO); These Physics past questions are for students who are sitting for the following examinations

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#1. The term torque means

A) the equilibrant of two concurrent forces

B) the moment of a force about an ads

C) the resultant of several forces acting on a body in equilibrium

D) two coplanar forces at right angle to each other

E) two equal and opposite forces whose lines of action do not coincide

#2. The lower and upper fixed points of a mercury-in-glass thermometer are marked X and 180 mm respectively. On a particular day the mercury meniscus in the thermometer rises to 60mm. If the corresponding reading on a Celsius scale is 20 ° C, what is the value X?

A) 6.0mm

B) 18.0mm

C) 30.0mm

D) 60.0mm

E) 120.0mm

#3. A waterfall is 6.30m high. What is the change in temperature of a quantity of water that falls from the top to the bottom of the waterfall? (Neglect heat losses to the surroundings, take g as 10 ms-2 and specific heat capacity of weather as 4200,J kg-1K-1

A) 0.15°C

B) 1.50°C

C) 15.00°C

D) 21.00 °C

E) 50.00°C

#4. A body on the ground is acted on by a force of 10N at a point P as shown in the fig above. What force is needed to stop the body from moving eastwards

A) 5N in the direction of east

B) 5N in the diretion of west

C) 5V3N in the direction of west

D) 10N in the southwest direction

#5. The total resistance measured at PQ in the diagram above is

A) 18.0Ω

B) 11.0Ω

C) 4.0Ω

D) 2.0Ω

#6. In the AC circuit diagram above, the resonance frequency is

A) 5000π Hz

B) 2500π Hz

C) 5000/π Hz

D) 2500/π Hz

#7. In a nuclear fusion experiment, the loss of mass amounts to 1.0 x 10-6kg. The amount of energy obtained from the fusion is

A) 3.0 x 10-4J

B) 3.0 x 10-1J

C) 9.0 x 104J

D) 9.0 x 1010J

#8. In photoelectric effect, electrons will leave the metal surface when illuminated by light of appropriate frequency if the photon energy is

A) greater than the work function

B) less than the work function

C) equal to the work function

D) equal to the maximium kinetic energy of the electron

#9. A parallel plate capacitor has a common plate area of 5 x 10-8m2 and plate separation of 2 x 103m, Assuming free space, What is the capacitance? [o = 9.0 X 10-12C2N-1m-2]

A) 2.25 x 10-17F

B) 4.50 x 10-17F

C) 2.25 x 10-16F

D) 4.50 x 10-16F

#10. The iron core of an induction coil is made from bundles of wire so as to

A) minimize eddy-currents

B) generate eddy-current

C) prevent sparking at the contact breaker

D) get the greatest posible secondary voltage

#11. A transformer which can produce 8V from a 240v a.c. supply, has an efficiency of 80%. If the current in the secondary coil is 15A, calculate the current in the primary coil.

A) 0.625A

B) 1.600A

C) 2.500A

D) 6.250A

#12. The electrochemical equivalent of a metal is 1.3 x 10-7kgC-1. The mass of the metal which 2.0 x 104C of electricity will deposit from a suitable electrolyte is

A) 6.5 x 10-2kg

B) 2.6 x 10-2kg

C) 6.5 x 10-3kg

D) 2.6 x 10-3kg

#13. Which of the following are true about the infra-red radiation? i. it is invisible ii. it is called heat ray iii. its frequency is higher than that of blue light iv. it travels as a transverse wave

A) i, ii, iii and iv

B) i, ii, iv only

C) i, iii, iv only

D) ii, iii, iv only

#14. An ebonite rod rubbed with fur attracts a glass rod rubbed with silk because

A) ebonite has a negative charge while glass has a positive charge

B) ebonite has a positive charge while glass has a negative charge

C) both have negative charges

D) both have positive charges

#15. Which of the following can be used to reduce local action in a Laclanche cell?

A) A carbon rod as the positive pole

B) Pure zinc as the negative pole

C) Potassium permanganate solution in contact with the positive pole

D) common salt solution

#16. Find the work done in moving a 2 C charge between two points X and Y in an electric field if the potential difference is 100 volts

A) 50J

B) 100J

C) 200J

D) 400J

#17. An object 0 lies at a distance m in front of concave mirror of focal length f. If m < f, then the final image obtained will be

A) virtual and diminished

B) magnified and erect

C) real and inverted

D) diminished and erect

#18. An object is placed in front of two plane mirrors inclined at an angle of 0o. If the total number of images formed is 7, Find the value of

A) 30o

B) 45o

C) 51o

D) 90o

#19. The most suitable type of mirror used for the construction of the search light is the

A) concave mirror

B) convex mirror

C) spherical mirror

D) parabolic mirror

#20. The displacement d produced in a glass block of thickness t and refractive index n when an object is viewed through it is

A) t – n

B) t (1 + 1/n)

C) t (1-1/n)

D) t (1/n - 1)

#21. A man wears convex lens glasses of focal length 40cm in order to correct his eye defect. instead of the optimum 25cm, his least distance of distinct vision is

A) 14cm

B) 28cm

C) 75cm

D) 150cm

#22. One valid assumption of the kinetic theory of gasses is the

A) the molecules of a gas are constantly in a state of motion and the number of collision remains constant

B) the number of molecule of gas increases with increasing pressure

C) as the temperature increases, the number of collision made by the gas molecule remains constant

D) the molecules of gas are all identical and are very small in size

#23. The physical properties of sound waves can best be described by

A) reflection and diffraction

B) polarization and reflection

C) polarization and diffraction

D) polarization and refraction

#24. In a closed organ pipe producing a musical note, an antinode will always be produced at

A) the closed end

B) the open end

C) the middle

D) all the parts of the pipe

#25. A steel wire of length 0.50m is stretched between two fixed points and its fundamental frequency is 200Hz. The speed of the wave in the wire is

A) 100ms-1

B) 120ms-1

C) 200ms-1

D) 250ms-1

#26. In a resonance tube experiment, if the fundamental frequency of the vibrating air column is 280Hz, the frequency of the third overtone is

A) 70Hz

B) 840Hz

C) 1120Hz

D) 1960Hz

#27. The linear expansivity of brass is 2 x 10-5C-1. If the volume of a piece of brass is 15.00cm3 at 00C, What is the volume at 100oC?

A) 16.03cm3

B) 16.00cm3

C) 15.09cm3

D) 15cm3

#28. A gas has a volume of 100cm3 at 27oC. If it is heated to temperature T until a final volume of 120cm3 is attained, calculate T

A) 33oC

B) 60oC

C) 87oC

D) 114oC

#29. How many grams of water at 17oC must be added to 42g of ice at 0oC to melt the ice completely? [specific latent heat of fusion of ice = 3.4 x 105Jkg-1, specific heat capacity of water = 4200Jkg-1k-1]

A) 200g

B) 300g

C) 320g

D) 400g

#30. A vapour is said to be saturated when

A) more molecules return to the liquid than the amount that left it

B) a dynamic equilibrium exists between the molecules of the liquid and the vapour molecules at a given temperature

C) the vapour pressure is equal to the atmospheric pressure

D) all molecules are moving with the same speed in all directions at a given temperature

#31. The tendon in a man's leg is 0.01m long. If a force of 5N stretches the tendon by 2.0 x 10-5m, calculate the strain on the muscle.

A) 5 x 106

B) 5 x 102

C) 2 x 10-3

D) 2 x 10-7

#32. Which of these statements are correct for the pressures in liquids? i. pressure in a liquid at a point acts equally in all directions. ii. pressure increases with depth. iii. pressure at a depth depends on the shape of the container. iv. pressure at the same depth in different liquids are proportional to the density at different liquids.

A) i, ii, iii only

B) i, ii, iv only

C) i, iii, iv only

D) ii, iii, iv only

#33. The atmospheric pressure due to water is 1.3 x 106Nm-2. What is the total pressure at the bottom of an ocean 10m deep? [Density of water = 1000kgm-3, g = 10ms-2]

A) 1.3 x 107Nm-2

B) 1.4 x 106Nm-2

C) 1.4 x 105Nm-2

D) 1.0 x 10 5Nm-2

#34. A solid of weight 0.600N is totally immersed in oil and water respectively. If the upthrust of oil is 0.210N and the relative density of oil is 0.875. Find the upthrust in water.

A) 0.600N

B) 0.360N

C) 0.240N

D) 0.180N

#35. The force of attraction between two point masses is 10-4N when the distance between them is 0.18m. If the distance is reduced to 0.06m, calculate the force.

A) 1.1 x 10-5N

B) 3.3 x 10-5N

C) 3.0 x 10-4N

D) 9.0 x 10-4N

#36. A uniform meter rule weighing 0.5N is to be pivoted on a knife-edge at the 30cm-mark. where will a force of 2N be placed from the pivot to balance the meter rule?

A) 95cm

B) 25cm

C) 20cm

D) 5cm

#37. A man whose mass is 80kg climbs a staircase in 20s and expends power of 120W. Find the height of the staircase.[g = 10ms-2]

A) 1.8m

B) 2.0m

C) 2.5m

D) 3.0m

#38. A parachute attains a terminal velocity when

A) its density is equal to the density of air

B) the viscous force of the air and the upthrust completely counteract its weight

C) it expands as a result of reduced external pressure

D) the viscous force of the air is equal to the sum of the weight and upthrust

#39. In a wheel and axle mechanism the diameters of the wheel and axle are 40cm and 8cm respectively. Given that the machine is 80% efficient, what effort is required to lift a load of 100N?

A) 20N

B) 25N

C) 50N

D) 80N

#40. The velocity of a sound wave at 27oC is 360ms-1. Its velocity at 127oC is

A) 120√3 ms-1

B) 240 ms-1

C) 240√3 ms-1

D) 720√3 ms-1

#41. The physical quantity that has the same dimensions as impulse is

A) energy

B) momentum

C) surface tension

D) pressure

#42. A ball is moving at 18ms-1 in a direction inclined at 60o to the horizontal. The horizontal component to its velocity is

A) 9√3ms-1 ·

B) 6√3ms-1 ·

C) 8√3ms-1 ·

D) 9ms-1 ·

#43. In free fall, a body of mass 1kg drops from a height of 125m from rest in 5s. How long will it take another body of mass 2kg to fall from rest from the same height? [g = 10ms-1·]

A) 5s

B) 10s

C) 12s

D) 15s

#44. A ball of mass 0.15kg is kicked against a rigid vertical wall with a horizontal velocity of 50ms-1. If it rebounced with a horizontal velocity of 30ms-1, calculate the impulse of the ball on the ball.

A) 3.0Ns

B) 4.5Ns

C) 7.5Ns

D) 12.0Ns

#45. A bullet fired at a wooden block of thickness 0.15m manages to penetrate the block. If the mass of the bullet is 0.025kg and the average resisting force of the wood is 7.5 x 103N, calculate the speed of the bullet just before it hits the wooden block.

A) 450ms-1

B) 400ms-1

C) 300ms-1

D) 250ms-1

#46. A ball is dropped from the top of a tower. Due to air resistance,it reaches terminal velocity. Which of the following statement(s) about its motion is/are correct? i. The acceleration of the ball is zero. ii. The net force on the ball is zero. iii. The velocity of the ball increases.

A) i only

B) i and ii only

C) ii and iii only

D) i, ii and iii

#47. A body moving in a circle at constant speed has i. a velocity tangent to the circle ii. a constant kinetic energy ii. an acceleration directed towards the circmference of the circle ii. an acceleration directed towards the circumference of the circle. Which of the statements above are correct?

A) i and ii only

B) ii and iii

C) ii and iii only

D) i and iii only

#48. A body of mass 200g and specific heat capacity 0.4Jg-1k-1 cools from 37oC to 31oC. Calculate the quantity of the heat released by the body.

A) 4800J

B) 1200J

C) 480J

D) 202J

#49. It is always not possible to determine exactly and simultaneously the position and momentum of a particle. This statement is known as the

A) De broglie's law

B) Heisenberg's uncertainty principle

C) Compton effect

D) Frank-Hertz experimental law

E) Wave particle paradox

#50. The diagram above represents a section of a pair of vernier calipers. The reading on the instrument is

A) 5.22cm

B) 5.24cm

C) 5.26

D) 5.35

#51. The process of increasing the energy of an atom via inelastic collision with an electron is known as

A) ionization

B) excitation

C) field emission

D) photoemission

E) thermonic emission

#52. The frictional effect between the layers of a moving fluid is called

A) capillarity

B) turbulence

C) diffusion

D) osmosis

E) viscosity

#53. An electron is accelerated from rest through a potential difference of 70kV in a vacuum. Calculate the maximum speed acquired by the electron (electronic charge = -1.6 x 10-19; mass of an electron = 9.1 x 10-31kg)

A) 3.00 x 108ms-1

B) 2.46 x 108ms-1

C) 1.57 x 108ms-1

D) 1.32 x 108ms-1

E) 1.11 x 108ms-1

#54. Lenz's law of electromagnet states that

A) the induced charge is constant for a fixed change of force

B) a force is exerted on a current-carrying conductor in a magnetic field

C) the magnitude of the induced e.m.f in a circuit is proportional to the rate of change of the number of lines of force linking the circuit

D) the induced current in a conductor is in such a direction as to oppose the change producing it

E) e.m.f. is induced in a circuit whenever there is a change in the magnetic flux linked with the circuit

#55. A proton of charge 1.6 x 1019C is projected into a uniform magnetic field of flux density with a constant speed of 1.6 x 106ms-1, calculate the magnitude of the force exerted on it by the field

A) 0.0N

B) 2.0 x 10-21N

C) 1.3 x 10-17N

D) 5.1 x 10-14N

E) 2.3 x 1013N

#56. The direction of the magnetic field at a point in the vicinity of a bar magnetic is

A) along the line joining the point to the neutral point

B) always away from the south pole of the magnet

C) opposite the direction of theresultant field at that point

D) always towards the north pole of the magnet

E) the direction towards which the north pole of a compass needle would point

#57. Which of the following are both mechanical and transverse?

A) infra-red rays

B) gamma rays

C) sound waves

D) water waves

E) micro waves

#58. The gravitational force of the moon is one-sixth that of the earth. If a body weighs 6.0N on the moon. Calculate its weight on the earth

A) 36.0N

B) 12.0N

C) 6.0N

D) 2.0N

E) 1.0N

#59. In the electrical method of magnetisation, the polarity of the magnet depends on the

A) amount of current passed

B) direction of current

C) magnetic material used

D) size of the magnetic material

E) orientation of the magnetic material in space

#60. A lantern gives an image of 3m square of a slide 7.62cm square on a screen. If the screen is 10m from the projection lens of the lantern, calculate the focal length of the lens

A) 40.3cm

B) 26.1cm

C) 24.8cm

D) 0.7cm

E) 0.3cm

#61. the shortest length of the air column in a resonance tube at resonance is 0.12m and the next resonance length is 0.37m. calculate the frequency of vibration given that the speed of sound in air is 340m-1

A) 1360Hz

B) 694Hz

C) 680Hz

D) 34Hz

E) 340Hz

#62. A sonometer wire under a tension of N10N, produces a frequency of 250Hz when plucked. Keeping the length of the wire constant, the tension is adjusted to produce a new frequency of 350Hz. Calculate the new tension

A) 39.2N

B) 19.6N

C) 14.2N

D) 7.4N

E) 5.1N

#63. Calculate he wavelength of a note which is one octave lower than a note of 256Hz in a medium in which the speed of sound is 352ms-1

A) 0.69m

B) 1.38m

C) 2.75m

D) 5.50m

E) 9.30m

#64. The phenomenon which occurs when light changes direction as it passes from one medium to another is called

A) reflection

B) polarisation

C) interference

D) diffraction

E) refraction

#65. What is the image distance of an object placed at a distance of 2f from a converging lens of focal length f?

A) f/4

B) f/2

C) f

D) 2f

E) 4f

#66. An astronomical telescope having an objective of focal length 100cm and an eyepiece of focal length 10cm is used in normal adjustment, calculate the separation of the lenses

A) 0.10m

B) 0.90cm

C) 1.10m

D) 1.80m

E) 2.20m

#67. A waterfall is 1.260m high. Calculate the change in temperature of a quantity of water that falls from the top to the bottom of the waterfall. (Neglect heat losses to the surroundings, take g as 10m-2 and specific heat capacity of water as 4200Jkg-1K-1)

A) 0.3oC

B) 3.0oC

C) 33.3oC

D) 42.0oC

E) 100.0oC

#68. A piece of metal is heated until it becomes red-hot, it is then quickly transferred into a beaker containing boiling water. What effect will this have on the boiling water?

A) the boiling water rises slightly

B) the boiling point rises sharply

C) the rate of vaporisation of the boiling water increases

D) the boiling point first rises and then falls

E) neither the boiling point nor the rate of vaporisation increases

#69. Question 81 A 90-W immersion heater is used to supply energy for five minutes. The energy supplied is used to completely melt 180g of a solid at is melting point. Neglecting energy losses to the surroundings, calculate the specific latent heat of fusion of the solid

A) 0.5Jg-1

B) 2.5Jg-1

C) 15.0Jg-1

D) 450.0Jg-1

E) 150Jg-1

#70. If an ebonite rod is rubbed with fur

A) both the ebonite rod and the fur will be negatively charged

B) the ebonite rod will be positively charged while the fur will have no charge

C) there will be electron transfer only if the ebonite rod is earthed

D) the ebonite rod will be negatively charged while the fur will be positively charged

E) the ebonite rod will be positively charged while the fur will be negatively charged

#71. An eclipse of the sun by the moon occurs when the sun, the moon and the earth are in a straight line and the

A) earth casts a shadow on the moon

B) moon casts a shadow on the sun

C) moon is between the sun and the earth

D) earth is between the sun and the moon

E) sun is between the moon and the earth

#72. If the cubic expansivity of brass between 27oC and 100oC is 5.7 x 10-5K-1, What is its linear expansivity?

A) 2.85 x 10-5K-1

B) 1.90 x 10-5K-1

C) 1.86 x 10-5K-1

D) 1.70 x 10-5K-1

E) 1.63 x 10-5K-1

#73. Air at temperature 527oC and pressure 30 atmospheres is admitted into the cylinder of an engine. Calculate the pressure of the gas when it has expanded to 5 times its volume and cooled to 127oC as it leaves the engine

A) 1.5 atmospheres

B) 2.5 atmospheres

C) 3.0 atmospheres

D) 12.8 atmospheres

E) 15.0 atmospheres

#74. The inside of a vacuum flak is usually coated with silver to reduce heat loss by

A) evaporation

B) radiation

C) conduction

D) convention

E) condensation

#75. Dry oxygen is trapped by a pellet of mercury in a uniform capillary tube which is sealed at one end. The length of the column of oxygen at 27oC is 50cm. if the pressure of the oxygen is constant, at what temperature will the length be 60cm?

A) 360.0oC

B) 240.6oC

C) 237.0oC

D) 87.0oC

E) 36oC

#76. An object is heated from 30oC to 57oC. The increases in its temperature on the kelvin scale is

A) 17k

B) 27k

C) 81k

D) 246k

E) 300k

#77. The lower and upper fixed points of a mecury-in-glass thermometer are marked Y and 180mm respectively. On a particular the mecury meniscus in the thermometer rises to 45mm. If the corresponding reading on a scale is 10o, calculate the value of Y.

A) 4mm

B) 18mm

C) 30mm

D) 135mm

E) 450mm

#78. A piece of brass of mass 170kg has its temperature raised from 0oC to 30oC. Calculate its increase in volume, given the density of brass at 0oC as 8.5 x 103kgm3 and its cubic expansivity as 5.7 x 10-1k1

A) 3.4 x 10-5m3 0

B) 4.3 x 10-5m3

C) 3.4 x 10-5m3

D) 3.4 x 10-3m3

E) 3.4 x 1-2m3

#79. The average kinetic energy of the molecules of a perfect gas is directly proportional to the

A) pressure exerted by the gas

B) volume of the gas molecule

C) kelvin temperature of the gas

D) volume of the gas container

E) celcius temperature of the gas

#80. I the box is pulled from P to Q, which of the following expresses the velocity ratio of the inclined plane?

A) PR/PQ

B) OR/PQ

C) OR/PR

D) PQ/PR

E) PQ/QR

#81. The earth is not a perfect sphere because its equatorial axis is longer than the polar axis. where on the earth's surface would an object have its greatest weight?

A) half way between the equator and the north pole

B) near the equator

C) half way between the equator and the south pole

D) at either pole

E) at the equator

#82. A piece of stone attached to one end pf string is whirled round in a horizontal circle. When the string is suddenly cut, the stone will

A) move towards te centre of the circle

B) stop moving immediately

C) move along a circular path of smaller radius

D) fly off in a direction tangential to the circular path

E) acquire greater centripetal force

#83. The term torque means

A) the moment

B) the resultant of several forces acting on a body in equilibrum

C) two equal and oposite forces whose lines of action do not coincide

D) two coplaner forces at right angles to each other

E) the equilibrant of two concurrent forces

#84. A rectangular block of wood floats in water with two-thirds of its volume immersed. When placed in another liquid, it floats with half of its volume immersed. Calculate the relative density of the liquid

A) 1.43

B) 1.33

C) 1.00

D) 0.83

E) 0.75

#85. As the end Q of the plank is raised, the component of W, normal to plank, will

A) increase

B) decrease

C) remain the same

D) be slightly greater than W

E) be independent of w

#86. which of the following pairs of physical quantities comprises vectors?

A) capacitance and inductance

B) force ratio and velocity ratio

C) friction and momentum

D) energy and power

E) electric field potential and electric field intensity

#87. plane as 63cm of HG while a ground observer records a reading of 75cm of Hg with his barometer. assuming that the density of air is constant, calculate the height of the plane above the ground. (Take the relative densities of air and mecury as 0.00136 and 13.6 respectively

A) 120m

B) 138m

C) 1200m

D) 274m

E) 120,000m

#88. A ball of mass 5.0kg hits a smooth vertical wall normally with a speed of 2ms-1 and rebounds with the same speed. Determine the impulse experienced by the ball

A) 20.0kg ms-1

B) 10.0kg ms-1

C) 5.0kg ms-1

D) 1.3kg ms-1

E) 0.0kg ms-1.

#89. The images formed by a diverging lens are always

A) diminished, virtual and inverted

B) diminished inverted and real

C) diminished, virtual and erect

D) magnified, virtual and erect

E) magnified, real and inverted.

#90. Two radioactive elements A and B have half-lives of 100 and 50 years respectively. Samples of A and B initially contain equal amounts/number of atoms. What is the ratio of the number of the remaining atoms of A to that of B after 200 years?

A) 4 : 1

B) 2 : 1

C) 1 : 1

D) 1 : 2

E) 1 : 4

#91. Which of the following explains the concave meniscus of water in a glass tube?

A) The adhesion between water and glas is greater than the cohesion between water molecules

B) The cohesion between water molecule is greater than the adhesion between glass and water

C) The molecules of water in the glass are moving faster than the molecules in the other parts

D) The molecules of water at the water-air boundary are often attracted to the center of the tube

E) The weight of the water pulls the central part of the surface down

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Physics Past Questions v23 for (JAMB/WAEC/NECO)

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Physics Past Questions v23 for (JAMB/WAEC/NECO)

Results

#1. The term torque means

#2. The lower and upper fixed points of a mercury-in-glass thermometer are marked X and 180 mm respectively. On a particular day the mercury meniscus in the thermometer rises to 60mm. If the corresponding reading on a Celsius scale is 20 ° C, what is the value X?

#3. A waterfall is 6.30m high. What is the change in temperature of a quantity of water that falls from the top to the bottom of the waterfall? (Neglect heat losses to the surroundings, take g as 10 ms-2 and specific heat capacity of weather as 4200,J kg-1K-1

#4. A body on the ground is acted on by a force of 10N at a point P as shown in the fig above. What force is needed to stop the body from moving eastwards

#5. The total resistance measured at PQ in the diagram above is

#6. In the AC circuit diagram above, the resonance frequency is

#7. In a nuclear fusion experiment, the loss of mass amounts to 1.0 x 10-6kg. The amount of energy obtained from the fusion is

#8. In photoelectric effect, electrons will leave the metal surface when illuminated by light of appropriate frequency if the photon energy is

#9. A parallel plate capacitor has a common plate area of 5 x 10-8m2 and plate separation of 2 x 103m, Assuming free space, What is the capacitance? [o = 9.0 X 10-12C2N-1m-2]

#10. The iron core of an induction coil is made from bundles of wire so as to

#11. A transformer which can produce 8V from a 240v a.c. supply, has an efficiency of 80%. If the current in the secondary coil is 15A, calculate the current in the primary coil.

#12. The electrochemical equivalent of a metal is 1.3 x 10-7kgC-1. The mass of the metal which 2.0 x 104C of electricity will deposit from a suitable electrolyte is

#13. Which of the following are true about the infra-red radiation? i. it is invisible ii. it is called heat ray iii. its frequency is higher than that of blue light iv. it travels as a transverse wave

#14. An ebonite rod rubbed with fur attracts a glass rod rubbed with silk because

#15. Which of the following can be used to reduce local action in a Laclanche cell?

#16. Find the work done in moving a 2 C charge between two points X and Y in an electric field if the potential difference is 100 volts

#17. An object 0 lies at a distance m in front of concave mirror of focal length f. If m < f, then the final image obtained will be

#18. An object is placed in front of two plane mirrors inclined at an angle of 0o. If the total number of images formed is 7, Find the value of

#19. The most suitable type of mirror used for the construction of the search light is the

#20. The displacement d produced in a glass block of thickness t and refractive index n when an object is viewed through it is

#21. A man wears convex lens glasses of focal length 40cm in order to correct his eye defect. instead of the optimum 25cm, his least distance of distinct vision is

#22. One valid assumption of the kinetic theory of gasses is the

#23. The physical properties of sound waves can best be described by

#24. In a closed organ pipe producing a musical note, an antinode will always be produced at

#25. A steel wire of length 0.50m is stretched between two fixed points and its fundamental frequency is 200Hz. The speed of the wave in the wire is

#26. In a resonance tube experiment, if the fundamental frequency of the vibrating air column is 280Hz, the frequency of the third overtone is

#27. The linear expansivity of brass is 2 x 10-5C-1. If the volume of a piece of brass is 15.00cm3 at 00C, What is the volume at 100oC?

#28. A gas has a volume of 100cm3 at 27oC. If it is heated to temperature T until a final volume of 120cm3 is attained, calculate T

#29. How many grams of water at 17oC must be added to 42g of ice at 0oC to melt the ice completely? [specific latent heat of fusion of ice = 3.4 x 105Jkg-1, specific heat capacity of water = 4200Jkg-1k-1]

#30. A vapour is said to be saturated when

#31. The tendon in a man's leg is 0.01m long. If a force of 5N stretches the tendon by 2.0 x 10-5m, calculate the strain on the muscle.

#33. The atmospheric pressure due to water is 1.3 x 106Nm-2. What is the total pressure at the bottom of an ocean 10m deep? [Density of water = 1000kgm-3, g = 10ms-2]

#34. A solid of weight 0.600N is totally immersed in oil and water respectively. If the upthrust of oil is 0.210N and the relative density of oil is 0.875. Find the upthrust in water.

#35. The force of attraction between two point masses is 10-4N when the distance between them is 0.18m. If the distance is reduced to 0.06m, calculate the force.

#36. A uniform meter rule weighing 0.5N is to be pivoted on a knife-edge at the 30cm-mark. where will a force of 2N be placed from the pivot to balance the meter rule?

#37. A man whose mass is 80kg climbs a staircase in 20s and expends power of 120W. Find the height of the staircase.[g = 10ms-2]

#38. A parachute attains a terminal velocity when

#39. In a wheel and axle mechanism the diameters of the wheel and axle are 40cm and 8cm respectively. Given that the machine is 80% efficient, what effort is required to lift a load of 100N?

#40. The velocity of a sound wave at 27oC is 360ms-1. Its velocity at 127oC is

#41. The physical quantity that has the same dimensions as impulse is

#42. A ball is moving at 18ms-1 in a direction inclined at 60o to the horizontal. The horizontal component to its velocity is

#43. In free fall, a body of mass 1kg drops from a height of 125m from rest in 5s. How long will it take another body of mass 2kg to fall from rest from the same height? [g = 10ms-1·]

#44. A ball of mass 0.15kg is kicked against a rigid vertical wall with a horizontal velocity of 50ms-1. If it rebounced with a horizontal velocity of 30ms-1, calculate the impulse of the ball on the ball.

#45. A bullet fired at a wooden block of thickness 0.15m manages to penetrate the block. If the mass of the bullet is 0.025kg and the average resisting force of the wood is 7.5 x 103N, calculate the speed of the bullet just before it hits the wooden block.

#46. A ball is dropped from the top of a tower. Due to air resistance,it reaches terminal velocity. Which of the following statement(s) about its motion is/are correct? i. The acceleration of the ball is zero. ii. The net force on the ball is zero. iii. The velocity of the ball increases.

#47. A body moving in a circle at constant speed has i. a velocity tangent to the circle ii. a constant kinetic energy ii. an acceleration directed towards the circmference of the circle ii. an acceleration directed towards the circumference of the circle. Which of the statements above are correct?

#48. A body of mass 200g and specific heat capacity 0.4Jg-1k-1 cools from 37oC to 31oC. Calculate the quantity of the heat released by the body.

#49. It is always not possible to determine exactly and simultaneously the position and momentum of a particle. This statement is known as the

#50. The diagram above represents a section of a pair of vernier calipers. The reading on the instrument is

#51. The process of increasing the energy of an atom via inelastic collision with an electron is known as

#52. The frictional effect between the layers of a moving fluid is called

#53. An electron is accelerated from rest through a potential difference of 70kV in a vacuum. Calculate the maximum speed acquired by the electron (electronic charge = -1.6 x 10-19; mass of an electron = 9.1 x 10-31kg)

#54. Lenz's law of electromagnet states that

#55. A proton of charge 1.6 x 1019C is projected into a uniform magnetic field of flux density with a constant speed of 1.6 x 106ms-1, calculate the magnitude of the force exerted on it by the field

#56. The direction of the magnetic field at a point in the vicinity of a bar magnetic is

#57. Which of the following are both mechanical and transverse?

#58. The gravitational force of the moon is one-sixth that of the earth. If a body weighs 6.0N on the moon. Calculate its weight on the earth

#59. In the electrical method of magnetisation, the polarity of the magnet depends on the

#60. A lantern gives an image of 3m square of a slide 7.62cm square on a screen. If the screen is 10m from the projection lens of the lantern, calculate the focal length of the lens

#61. the shortest length of the air column in a resonance tube at resonance is 0.12m and the next resonance length is 0.37m. calculate the frequency of vibration given that the speed of sound in air is 340m-1

#62. A sonometer wire under a tension of N10N, produces a frequency of 250Hz when plucked. Keeping the length of the wire constant, the tension is adjusted to produce a new frequency of 350Hz. Calculate the new tension

#63. Calculate he wavelength of a note which is one octave lower than a note of 256Hz in a medium in which the speed of sound is 352ms-1

#64. The phenomenon which occurs when light changes direction as it passes from one medium to another is called

#65. What is the image distance of an object placed at a distance of 2f from a converging lens of focal length f?

#66. An astronomical telescope having an objective of focal length 100cm and an eyepiece of focal length 10cm is used in normal adjustment, calculate the separation of the lenses

#67. A waterfall is 1.260m high. Calculate the change in temperature of a quantity of water that falls from the top to the bottom of the waterfall. (Neglect heat losses to the surroundings, take g as 10m-2 and specific heat capacity of water as 4200Jkg-1K-1)

#68. A piece of metal is heated until it becomes red-hot, it is then quickly transferred into a beaker containing boiling water. What effect will this have on the boiling water?

#69. Question 81 A 90-W immersion heater is used to supply energy for five minutes. The energy supplied is used to completely melt 180g of a solid at is melting point. Neglecting energy losses to the surroundings, calculate the specific latent heat of fusion of the solid

#70. If an ebonite rod is rubbed with fur

#71. An eclipse of the sun by the moon occurs when the sun, the moon and the earth are in a straight line and the

#72. If the cubic expansivity of brass between 27oC and 100oC is 5.7 x 10-5K-1, What is its linear expansivity?

#73. Air at temperature 527oC and pressure 30 atmospheres is admitted into the cylinder of an engine. Calculate the pressure of the gas when it has expanded to 5 times its volume and cooled to 127oC as it leaves the engine

#74. The inside of a vacuum flak is usually coated with silver to reduce heat loss by

#75. Dry oxygen is trapped by a pellet of mercury in a uniform capillary tube which is sealed at one end. The length of the column of oxygen at 27oC is 50cm. if the pressure of the oxygen is constant, at what temperature will the length be 60cm?

#76. An object is heated from 30oC to 57oC. The increases in its temperature on the kelvin scale is

#77. The lower and upper fixed points of a mecury-in-glass thermometer are marked Y and 180mm respectively. On a particular the mecury meniscus in the thermometer rises to 45mm. If the corresponding reading on a scale is 10o, calculate the value of Y.