# An object of mass 1kg travelling in a straight line with a velocity of 10m//s collides with, and sticks to, a stationary wooden block of mass 5kg

38 views
in Physics
closed
An object of mass 1kg travelling in a straight line with a velocity of 10m//s collides with, and sticks to, a stationary wooden block of mass 5kg. Then, they both move off together in the same straight line. Calculate the total momentum just before the impact and just after the impact. Also, calculate the velocity of the combined object.

by (68.4k points)
selected by

Here, m_(1) = 1kg, u_(1)= 10m//s , m_(2) 5kg u_(2) = 0
Before impact, total momentum = m_(1)u_(1)+m_(2)u_(2)
or P_(1) = 1xx10+5xx0 = 10kg m//s
just after impact, total momentum remains the same, i.e.,
P_(2)=P_(1)=10 kg m//s
If v is velocity of the combined object,
then from P_(2)= (m_(1)+m_(2))v, v=p_(2)/(m_(1)+m_(2))= 10/((1+5))= 1.67 m//s`