Question

Two ice skaters, one with the mass of 40kg and the other with a mass of 0kg, push off against one another startingfrom a a stationary positiomn. After they have ouushed off, the relatice speedat which they separate is 1.5m/s. what is the speed of the 50kg skater?

Answer 1

The velocity of 50 kg skater is 0.67 m/s.

Step-by-step explanation:

Given that,

Mass of one ice skater = 40 kg

Mass of other ice skater = 50 kg

Speed of first = 1.5 m/s

Let the velocity of 40 kg and 50 kg skater be v and V respectively.

We need to calculate the velocity of 50 kg skater

Using law of conservation of momentum

As they start from rest , their initial momentum is zero.

`mv=m_(1)v_(1)+m_(2)v_(2)`

Put the value into the formula

`0=40v+50V`

`v=-(5V)/(4)`

Also relative velocity of separation is 1.5 m/s.

Using formula of relative velocity V'

`V'=V-v`

`1.5=V-v`

Put the value of v in to the formula

`1.5=V+(5V)/(4)`

`1.5=(9V)/(4)`

`V=(1.5*4)/(9)`

`V=0.67\ m/s`

Hence, The velocity of 50 kg skater is 0.67 m/s.