Incomplete question.The complete question is here
You go to the playground and slide down the slide, a 3.6m long ramp at an angle of 40 degrees with respect to horizontal. The pants that you've worn aren't very slippery; the coefficient of kinetic friction between your pants and the slide is 0.47. A friend gives you a very slight push to get you started.
How long does it take you to reach the bottom of the slide?
Answer:
t= 1.612 sec
Explanation:
Given Data
µk=0.47
D=3.6 m
Angle=40°
To find
t (Time)=?
Solution
a = g(sinΘ - µkcosΘ)
where
a is an acceleration
g is gravity constant
Θ is an angle
µk the coefficient of kinetic friction
So
a=9.8(sin40°- 0.47cos40°)
a= 2.771 m/s²
to find t(time)
t = √[2D/a]
t= √[2*3.6/2.771]
t= 1.612 sec