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5. A truck starts from rest and rolls down a hill with constant acceleration. It travels a
distance of 400 m in 20 s. Calculate the acceleration and the force acting on it if its
mass is 7 metric tonnes.

6.A force acts for 10 s on a body of mass 10 kg after which the force ceases and the
body describes 50 m in the next 5 s. Find the magnitude of the force.
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7.A ship of mass 3 × 10 kg and initially at rest can be pulled through a distance of 3 m
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by means of a force of 5 × 10 N. The water resistance is negligible. Find the speed
attained by the ship.
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8. A cricket ball of mass 150 g moving with a velocity of 15 ms is brought to rest by a
player in 0.05 s. Calculate the impulse and the average force exerted by the player.
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9. A hammer weighing 1 kg moving with the speed of 10 ms strikes the head of a nail
driving it 10 cm into a wall. Neglecting the mass of the nail, calculate (i) the acceleration
during impact (ii) the time interval of the impact and (iii) the impulse.
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10. A machine gun fires a bullet of mass 40 g with a speed of 1200 ms . The person
holding the gun can exert a maximum force of 144 N on it. What is the number of bullets
that can be fired from the gun per second?
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11.The initial speed of a body of mass 2.0 kg is 5.0 ms . A force acts for 4 s in the
direction of motion of the body. The force-time graph is shown in Fig. Calculate the
impulse of the force and the final speed of the body