Question

A ball of mass 1 kg strikes a wall at right angle and it rebounds 10 if its velocity changes from hundred metre per second to 50 metre per second then change in momentum is what​

Answer 1

change in momentum = Final momentum - Initial momentum

                                     = $mv_{f} - mv_{i}$

                                     = $m(v_{f} - v_{i})$

initial velocity = 100 ms-1

final velocity = -50ms-1 (because the final velocity is in opposite direction)

change in momentum = 1[(-50)-100)]

                                     = -150kgms-1

but if you take the direction of final velocity to be positive then initial velocity will be negative and change in momentum will be 150ms-1

Answer 2

Answer:

-150kgms-1

Explanation:

$m(v_{f} - v_{i}$

1(-50-100)

-150ms-1