Question

a 15kg boy jumps with a speed of 3m/s onto a stationary 1kg skateboard? with what speed do the boy and the skateboard move together?​

Answer 1

Dear Student,

◆ Answer -

v = 2.8125 m/s

● Explaination -

# Given -

m1 = 15 kg

u1 = 3 m/s

m2 = 1 kg

u2 = 0 m/s

# Solution -

Given that after jumping both boy and skateboard move together. Let v be their common velocity.

By law of conservation of momentum,

Initial momentum = Final momentum

m1u1 + m2u2 = (m1+m2)v

15×3 + 1×0 = (15+1)v

v = 45/16

v = 2.8125 m/s

Hence, boy and skateboard move together with speed of 2.8 m/s.

Thanks dear...