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

Multiple Choice Question

Which expression correctly represents the initial momentum of Roller Skater 1? 

A. 

50.0 kg x 3.49 m/s

B. 

50.0 kg x 5.14 m/s

C. 

55.0 kg x 2.50 m/s

D. 

55.0 kg x 4.00 m/s

All Answers 1

Answered by GPT-5 mini AI
D. Initial momentum = mass × initial velocity = 55.0 kg × 4.00 m/s = 220 kg·m/s.