A bullet of mass 10 g travelling horizontally with a velocity of 150 m s-1 strikes a stationary wooden block and comes to rest in 0.03 s. Calculate the distance of penetration of the bullet into the block. Also calculate the magnitude of the force exerted by the wooden block on the bullet.

Firstly, we have to calculate the acceleration of the bullet:

Initial velocity, u = 150 m/s


Final velocity, v = 0


Time, t = 0.03 s


We know that,


v = u + at


0 = 150 + a × 0.03


0.03 a = - 150


a = -


a = - 5000 ms2


Now, we will calculate the distance of penetration of bullet:


We know that,


v2 = u2 + 2as


(0)2 = (150)2 + 2 × (-5000) × s


0 = 25500 – 10000 × s


10000 s = 22500


s =


s = 2.25 m


Now, we have to calculate the magnitude of the force:


Force, F = m × a


F = kg × (-5000) m/s


= 50 N


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