Question

A father (mF = 85 kg) and his daughter (mD= 45 kg) stand on a flat frozen lake of negligible friction. They hold a 14 ­m­ long rope stretched between them. The father and daughter then pull the rope to bring them together. If the father is initially standing at the origin, how far from the origin will they meet?

Answer 1

Answer:

4.84615 m

Explanation:

Here the linear momentum is conserved and it is assumed that they will meet at the center of gravity of the system.

The center of gravity is given by

$R=\frac {1}{M}\sum _{i=1}^{n}m_ir _i$

where

i = Particle

m = Mass

r = Position

n = Number of particles

The father's location is taken as reference

$R=\frac{(0\times 85)+(45\times 14)}{85+45}=4.84615\ m$

The father will be 4.84615 m from the origin.