Question

if you jumped on a moving rollerboard, did you apply force for it to move backward?

Answer 1

Well, there's the friction force between your feet and the board. And if you know Newton's third law...

Answer 2

Welcome to openstudy!!!

Answer 3

U hv to use the law of conservation of momentum

Answer 4

By colliding between a stationary object and a moving object,

Answer 5

After collision stationary object will move and moving object will move with slower speed

Answer 6

Momentum of object 1 b4 collision + momentum of object 2 b4 collision = momentum of object 1 after collision + momentum of object 2 after collision

Answer 7

This is called conservation of momentum law

Answer 8

B4 collision
You hv no speed
Rollerboard has speed

Answer 9

After collision
Your speed=rollerboard speed

Answer 10

@shamim I think it's simpler to just use Newton's third law. Since the board must apply a friction force to your feet to get you moving, your feet must apply a force to the board.

Answer 11

I think we can use the knowledge of inertia to understand the fact .

Answer 12

U r correct too !! @agent0smith

Answer 13

Newtons third law of motion is easier to explain this fact.. agreed

Answer 14

I m agreed with u

Answer 15

You just have to remember that those two forces are both internal to the system, so like you said, momentum of the board-person system is conserved.

Answer 16

Yeah you could also use inertia - to get the person moving, the board must apply a force to them. Newton's third law again says the person must apply a force to the board.

Answer 17

Force acting on rollerboard by the man=force acting on man by rollerboard

Answer 18

But those 2 forces r opposit in direction