Answer:
The skater's speed after she stops pushing on the wall is 1.745 m/s.
Explanation:
Given that,
The average force exerted on the wall by an ice skater, F = 120 N
Time, t = 0.8 seconds
Mass of the skater, m = 55 kg
It is mentioned that the initial sped of the skater is 0 as it was at rest. The change in momentum of skater is :
[tex]\Delta p=m(v-u)\\\\\Delta p=mv[/tex]
The change in momentum is equal to the impulse delivered. So,
[tex]J=\Delta p=F\times t\\\\mv=F\times t\\\\v=\dfrac{Ft}{m}\\\\v=\dfrac{120\times 0.8}{55}\\\\v=1.745\ m/s[/tex]
So, the skater's speed after she stops pushing on the wall is 1.745 m/s.
