The question is incomplete, here is a complete question.
A sled slides along a horizontal surface for which the coefficient of kinetic friction is 0.25. Its velocity at point A is 8.0m/s and at point B is 5.0m/s.
Use the impulse-momentum theorem to find how long the sled takes to travel from A to B.
Answer : The sled takes time to travel from A to B is, 1.2 seconds.
Explanation :
Impulse-momentum theorem:
Impulse = Change in momentum
where,
m = mass
g = acceleration due to gravity =
= coefficient of kinetic friction = 0.25
= final velocity = 8.0 m/s
= initial velocity = 5.0 m/s
t = time
Now put all the given values in the above formula, we get:
Therefore, the sled takes time to travel from A to B is, 1.2 seconds.