Question

You are initially at rest at one end of a 3.00m platform (also initially at rest) that floats frictionlessly on a surface of slick oil. If you walk from one end of the platform to another with a constant velocity of 2.00m/s from one end of the platform to the other, what is the kinetic energy of the system just before you come to rest at the opposite end? ( you are 50kg, and the platform is 100kg)

Answer 1

@PaxPolaris do you know how to do this?

Answer 2

@kropot72

Answer 3

@iGreen

Answer 4

@arabpride

Answer 5

@Compassionate

Answer 6

@Jhannybean

Answer 7

is it 0?

Answer 8

if the system is you and the plank .... which is on a frictionless surface.... the center of mass of the system should not move while you walk from one end to the other.

so i think KE of the system should be 0

Answer 9

the total momentum would be 0 i think since the system is initally at rest

Answer 10

the center of mass doesnt move?

Answer 11

then how would you get to the other side you would be in the same place right

Answer 12

the center of mass of you plus the plank.... my own clumsy ways of saying net momentum =0


... you alone would have kinetic energy .... the plank alone shows KE ... but taken together as a system 0KE

Answer 13

that's my opinion anyhow...