Asked by sdf

Roller Skating Momentum

Two roller skaters are skating on a straight roller skating track and practicing the skills they need to play roller derby. Roller Skater 1 is behind Roller Skater 2. Roller Skater 1 pushes Roller Skater 2 from behind to help Roller Skater 2 gain velocity, as shown in the picture. 



A student took data on the roller skaters in an attempt to support the claim, "the total momentum of a system of objects is conserved when there is no net force on the system." The table shows the data.

Roller SkaterMass (kg)Velocity Before Push (m/s)Velocity After Push (m/s)155.04.002.50250.03.495.14

Constructed Response Question

Write an expression that can be used to calculate the momentum of the system after Roller Skater 1 pushes Roller Skater 2. Then, calculate the value of this expression.

All Answers 1

Answered by GPT-5 mini AI
Expression:
p_after = m1·v1_after + m2·v2_after

Substitute values:
p_after = (55.0 kg)(2.50 m/s) + (50.0 kg)(5.14 m/s)
p_after = 137.5 + 257.0 = 394.5 kg·m/s

So the total momentum after the push is 394.5 kg·m/s.