Question

3. A skater with an initial speed of 7.6 m/s is gliding across the ice. The coefficient of friction between the ice and the skae blades is μk=0.1.

a. Find acceleration of the skater
b. How foar will the skater travel before coming to rest

Answer 1

mass m

weight = m g = 9.81 m

friction force = 0.1 * weight
= 0.981 m

That is the entire horizontal force
so
F = m a
0.981 m = m a

a = 0.981
-------------------
how long to stop?
v = Vi - 0.981 t
0 = 7.6 - 0.981 t
t = 7.75 seconds to grind to a halt
d = Vi t - (1/2)(0.981) t^2
d = 7.6 (7.75) - .49 (7.75)^2
= 58.8 - 29.4
= 29.4 meters