Physics Jamb CBT 2

1. When the temperature of liquid increases, its surface tension

17. A test tube of radius 1.0cm is loaded to 8.8g. If is placed upright in water, find the depth to which it would sink

33. The pressure of a given mass of a gas changes from 200Nm-2 to 80Nm-2 while the temperature drops from 127°C to -73°C. The ratio of the final volume to the initial volume is

49. If tension is maintained on a stretched string of length 0.6m, such that its fundamental frequency of 220Hz is excited, determine the velocity of the transverse wave in the string.

2. A gas at a volume of V0 in a container at pressure P0 is compressed to one-fifth of its volume. What will be its pressure if the magnitude of its original temperature T is constant?

18. A piece of substance of specific head capacity 450JKg-1K-1 falls through a vertical distance of 20m from rest. Calculate the rise in temperature of the substance on hitting the ground when all its energies are converted into heat. [g = 10ms-2]

34. The thermometric substance of an absolute thermometer is

50. Blowing air over a liquid aids evaporation by

3. A 90cm uniform lever has a load of 30N suspended at 15cm from one of its ends. If the fulcrum is at the centre of gravity, the force that must be applied at its other end to keep it in horizontal equilibrium is

19.
I. A liquid boils when its saturated vapour pressure is equal to the external pressure
II. Dissolved substances in pure water lead to increase in the boiling point.
III. When the external pressure is increased, the boiling point increases.
IV. Dissolved substances in pure water decrease the boiling point.

Which combination of the above are peculiarities of the boiling point of a liquid?

35. A plane sound wave of frequency 85.5Hz and velocity 342ms-1 is reflected from a vertical wall. At what distance from the wall does the wave have antinode?

4. The temperature gradient across a copper rod of thickness 0.02m, maintained at two temperature junctions of 20°C and 80°C respectively is

20.The temperature gradient across a copper rod of thickness 0.02m, maintained at two temperature junctions of 20°C and 80°C respectively is

36. A gas with initial volume of 2 X 10-6m3 is allowed to expand to six times its initial value at constant pressure of 2 x 105Nm-2. The work done is

5. A hose of cross-sectional area 0.5m2 is used to discharge water from a water thank at a velocity of 60ms-1 in 20s into a container. If the container is filled completely, the volume of the container is

21. Calculate the mass of ice that would melt when 2kg of copper is quickly transferred from boiling water to a block of ice without heat loss;
Specific heat capacity of copper = 400JKg-1K-1
Latent heat of fusion of ice = 3.3 x 10^5JKg-1

37. The cost of running five 60 W lamps and four 100 W lamps for 20 hours if electrical energy cost #10.00 per kwh is

6. A force of 100N is used to kick a football of mass 0.8kg. Find the velocity with which the ball moves if it takes 0.8s to be kicked.

22. The equation of a wave travelling along the positive x-direction is given by;
y = 0.25 x 10^-3 sin (500t – 0.025x).
Determine the angular frequency of the wave motion.

38. A copper cube weighs 0.25 N in air, 0.17N when completely immersed in paraffin oil and 0.15 N when completely immersed in water. The ratio of upthrust in oil to upthrust in water is

7. A catapult used to hold a stone of mass 500g is extended by 20cm with an applied force F. If the stone leaves with a velocity of 40m/s, the value of F is

23. The lowest note emitted by a stretched string has a frequency of 40Hz. How many overtones are there between 40hz and 180Hz?

39. A wheel and axle is used to raise a load of 500 N by the application of an effort of 250 N. If the radii of the wheel and the axle are 0.4 cm and 0.1 cm respectively, the efficiency of the machine is

8. The inner diameter of a test tube can be measured accurately using a

24. The velocity ratio of a machine is 5 and its efficiency is 75%. What effort would be needed to lift a load of 150N with the machine?

40. The hydrostatic blood pressure difference between the head and the feet of a boy standing straight is 1.65 x 104 Nm-2. Find the height of the boy.
[ Density of blood = 1.1 x 103 kgm-3, g = 10ms-2]

9. Particles of mass 10-2kg is fixed to the tip of a fan blade which rotates with angular velocity of 100rad-1. If the radius of the blade is 0.2m, the centripetal force is

25. If the force and the velocity on a system are each reduced simultaneously by half, the power of the system is

41. A bodyweight 80N stands in an elevator that is about to move. The force exerted by the floor on the body as the elevator moves upward with an acceleration of 5 ms-2 is
[g = 10ms-2]

10. A lead bullet of mass 0.05kg is fired with a velocity of 200ms-1 into a lead block of mass 0.95kg. Given that the lead block can move freely, the final kinetic energy after impact is

26. A catapult used to hold a stone of mass 500g is extended by 20cm with an applied force F. If the stone leaves with a velocity of 40m/s, the value of F is

42. Two force each of 10N acts on a body, one towards the north and the other towards the east.
The magnitude and the direction of the resultant force are

11.
I. Temperature.
II. Density of air molecules
III. Pressure
IV. Pitch
Which of the above will affect the velocity of sound in the air

I. The frictional force is independent of the area of the surfaces in conduct
II. The frictional force depends on the nature of the surfaces in contact
III. The frictional force depends on the speed of sliding
IV. The frictional force is directly proportional to the normal reaction.

Which combination of the above is true of sliding friction?

43. A particle in circular motion performs 30 oscillations in 6 seconds. Its angular velocity is

12. A car of mass 800kg attains a speed of 25m/s in 20 secs. The power developed in the engine is

28. A thin wire with heavy weights attached to both ends is hung over a block of ice resting on two supports. If the wire cuts through the ice block while the block remains solid behind the wire, the process is called

44. The effects of a particle in a fluid attaining its terminal velocity is that the

13. When the brakes in a car are applied, the frictional force on the tyres is

29. A metal of mass 0.5kg is heated to 100°C and then transferred to a well-lagged calorimeter of heat capacity 80JK-1 containing water of heat capacity 420JK-1 at 15°C. If the final steady temperature of the mixture is 25°C, find the specific heat capacity of the metal.

45. The radiator of a motor car is cooled by

14. If the stress on a wire is 107NM-2 and the wire is stretched from its original length of 10.00 cm to 10.05 cm. The young’s modulus of the wire is

30. The resultant of two forces acting on an object is maximum if the angle between them is

46. Which of the following is a characteristic of stationary waves?

15. A solid weigh 10 .00 N in air, 6 N when fully immersed in water and 7.0 N when fully immersed in a liquid X. Calculate the relative density of the liquid, X.

31. The efficiency of a machine is always less than 100% because the

47. The property that is propagated in a travelling wave is

16. When temperature of a liquid increases, its surface tension

32. Which of the following consists entirely of vector quantities?

48. The time rate of loss of heat by a body is proportional to the