Question

A 54-kgkg woman and a 79-kgkg man stand 11 mm apart on frictionless ice.

1)

How far from the woman is their CMCM?

Express your answer using two significant figures.

2)

If each holds one end of a rope, and the man pulls on the rope so that he moves 3.0 mm , how far from the woman will he be now?

Express your answer using two significant figures.

3)

How far will the man have moved when he collides with the woman?

Express your answer using two significant figures.

Answer 1

1)

The COM formula for the system is,

Putting the values in above equation,

2)

As there is no external force on the system,

Therefore,

Putting all the values in the above equation,

3)

As there is no external force on the system, The centre of mass possition of man-woman system will remain at rest,

Therefore man moves by the distance = 11-6.53 =4.47mm