The collision between a geological hammer and a rock lying loose on the ground can be considered to be approximately elastic.
calculate the final speed of a 0.21-kg rock when it is struck by a 0.55-kg hammer moving with an initial speed of 5.2 m/s. the rock is initially at rest.

Answer

given,

mass of the rock ( m ) = 0.21 Kg

mass of hammer ( M ) = 0.55 Kg

initial speed of the hammer ( u ) =  5.2 m/s

final speed of the rock = ?

using energy of conservation

.....(1)

In elastic collision Kinetic energy is equal to final energy

....(2)

on solving both the equation for velocity of hammer

v' = 2.33 m/s

velocity of the rock

v = 3.37 m/s

i think the correct answer from the choices listed above is option c. when the kinetic energy of particles in a liquid state decreases

explanation:

their crystal patterns have been disrupted by stress