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BOOKS

1. CONCISE Physics - Middle School - 8

CHAPTERS

1. Matter

2. Physical Quantities and Measurement

3. Force and Pressure

4. Energy

5. Light Energy

6. Heat Transfer

7. Sound

8. Electricity

EXERCISES

1. Objective Questions

2. Short/Long Answer Questions

3. Numericals

Q1) A force of 30 N acts on a body and moves it through a distance of 5 m in the direction of force. Calculate the work done by the force.

Q2) A man lifts a mass of 20 kg to a height of 2.5 m. Assuming that the force of gravity on 1 kg mass is 10 N, find the work done by the man.

Q3) A body when acted upon by a force of 10 kgf moves to a distance 0.5 m in the direction of force. Find the work done by the force. Take 1 kgf = 10 N

Q4) Two bodies of same masses are placed at heights h and 2h. Compare their gravitational potential energy.

Q5) Find the gravitational potential energy of 2.5 kg mass kept at a height of 15 m above the ground. The force of gravity on mass 1 kg is 10 N.

Q6) The gravitational potential energy stored in a box of weight 150 kgf is 1.5 \times 10^4. Find the height of the box. Take 1 kgf = 10 N

Q7) The potential energy of a body of mass 0.5 kg increases by 100 J when it is taken to the top of a tower from ground. If force of gravity on 1 kg is 10 N, what is the height of the tower?

Q8) A body of mass 60 kg is moving with a speed 50 m\ s^{-1}. Find its kinetic energy.

Q9) A truck of mass 1000 kg, increases its speed from 36 km\ h^{-1} to 72 km\ h^{-1}. Find the increase in its kinetic energy.

Q10) A car is moving with a speed of 15 km\ h^{-1} and another identical car is moving with a speed of 30 km\ h^{-1}. Compare their kinetic energy.

Q11) A pump raises water by spending 4\times10^5\ J of energy in 10 s. Find the power of pump.

Q12) It takes 20s for a girl A to climb up the stairs while girl B takes 15 s for the same job.

(a) Compare the work done.

(b) Compare the power spent by then.

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Mathematics

Physics

CONCISE Physics - Middle School - 8

Matter

Physical Quantities and Measurement

Force and Pressure

Energy

Light Energy

Heat Transfer

Sound

Electricity

Objective Questions

Short/Long Answer Questions

Numericals

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Race To Space

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