Question

A truck of mass 1200 kg is moving with a speed of 7 ms- when
it collides with a second truck of mass 1600kg which is
stationary. If the two trucks are automatically coupled together
on impact, the speed in metres per second with which
combination moves is​

Answer 1

Answer:

For this we should use the conservation of momentum

initial momentum is 1200 *7=8400 Kgm/s

finally momentum is (1200+1600) *v

from conservation of momentum we can say it is equal to 8400

v=8400/2800=3 m/s

Explanation: