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Suresan.AP

VAELS INTERNATIONAL SCHOOL INJAMBAKKAM

GRADE X PHYSICS WORKSHEET-3

Force+ Work power & Energy

Name of the Student: Date of submission:

1. A force is applied on a body of mass 20 kg moving with a velocity 40 m/s. The body attains a velocity of 60 m/S.

calculates the work done by the body. [2013, 2 mark]

2. A girl of mass 35 kg climbs up the from first floor of a building at a height 4 m above the ground to the third floor at a

height 12 m above the ground. What will be the increase in the gravitational potential energy? [2013,2 mark]

3. (i)State the principle of conservation of the energy (ii). Name the form of energy, which a body may possess when it is

not in motion. [2013,3 marks]

4. A ball is placed on a compressed spring. When the spring is released, the ball is observed to fly away.

(i). what form of energy does the compressed spring possess? (ii). Why does the ball fly away? [2012, 2 marks]

5. (i). State the energy the transformation, taking place in a solar cell. (ii). Name one disadvantage of using solar cell

[2012, 2 Mark]

6. A body of mass 0.2 kg falls from a height 10 m to height of 6 m above the ground. Find the change in kinetic energy of

the body. ( g= 10 m/s2) [2012, 2mark]

7. A moving body weighing 400 N possesses 500 j of kinetic energy. Calculate the velocity of the body (g = 10 m/s2)

[2012, 3mark]

8. A ball of mass 200 g falls from height of 5 m. What will be its kinetic energy, when it just reaches the ground? ( g = 10

m/s2) [2011, 2 Mark]

9. What is meant by energy degradation? [2012, 2mark]

10. Calculate the work done by a man carrying a load on his head and moving along a horizontal platform for 50m,

ignoring friction. Reason you answer. [2011, 3 Mark]

11. Draw a diagram to show the energy changes in an oscillating simple pendulum. Indicate in the diagram how the total

mechanical energy remains constant during the oscillation. [2011, 3 mark]

12. A body id acted upon by a force State two conditions under which the work done is zero. [2010, 2 Mark]

13. A body of mass 50 kg has a momentum of 300 kg m/s. Calculate (i). kinetic energy of the body (ii). the velocity of the

body. [2010, 3 Mark]

14. What is the SI unit of energy? How is electron volt (eV) related to it? [2009, 2 mark]

15. State the energy changes taking place in (i). photo-voltaic cell (ii). electromagnet [2009, 2 mark]

16. A body of 5 kg is moving with a velocity 10 m/S. what is the ratio of its initial kinetic energy to final kinetic energy if

its mass doubled and velocity halved [2009, 3 Mark]

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Suresan.AP

17. A spring is kept compressed by a small trolley of mass 0.5 kg lying on a smooth horizontal surface as shown in the

diagram. When the trolley is released, it is found to move at a speed of 2 m/s. what was the potential energy of the

spring when it was compressed? [2010, 2 Mark]

18. Energy of 6.4 kJ causes a displacement of 64 m of a body in the direction of the force in 2.5 s. calculate (i). the force

applied (ii). power in horse power. [2009, 3 Mark]

19. (i). Name the one factor on which the position of the centre of gravity of a body depends.

(ii). What is the SI unit of moment of force? [2015, 2 Mark]

20. Name the factors affecting the turning effect of force. [2015, 2 Mark]

21. When a body is placed on a table top, it exerts a force equal to its weight downwards on the table top, but does not

move or fall.

(i). name the force exerted by the table top. (ii). What is the direction of this force? [2015, 2 mark]

22. (i). define equilibrium (ii). When the beam of a beam balance is, is balanced in horizontal position, it in

________equilibrium. [2015,2 Mark]

23. How is work done by a force is measured when the force

(i). is in the direction of the displacement (ii). Is at an angle θ to the direction of displacement. [2015, 2 mark]

24. State the energy changes in the following while in use

(i). Burning a candle (ii). A steam engine [2015, 2 Mark]

25. (i). 1 eV = ______ J (ii). 1 kWh = ____________J [2015, 2 Mark]

26. Explain the motion of a planet around the Sun in a circular path [2015. 2 Mark]

27. Rajan exerts a force of 150 N in pulling a cart at a constant speed of 10 m/ s. Calculate the power exerted. [2015, 2 ]

28. (i). Name the physical quantity measured in terms of Horse Power. (ii). A nut is opened by wrench of length 20 cm.

If the least force required is 2 N, find the moment of force required to loosen the nut. (iii). Explain why the work done

by a fielder when he takes a catch is negative. [2015, 4 Mark]