How Do Friction and Centripetal Force Affect Motion on a Slide and a Rotor Ride?

AI Thread Summary
The discussion focuses on calculating the coefficient of kinetic friction for a child sliding down a 29-degree incline, where her speed is two-thirds of what it would be on a frictionless slide. Participants emphasize the importance of using energy conservation principles and drawing free body diagrams to analyze forces acting on the child. The conversation also touches on the physics of rotor rides, explaining the sensation of being pressed against the wall due to the difference in reference frames between the rider and an observer on the ground. The need for participants to demonstrate their progress before receiving guidance is highlighted. Overall, the thread provides insights into the application of physics concepts to real-world scenarios.
Vlyandra
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I feel like there's not enough information to solve this:

A child slides down a slide with a 29 degree incline, and at the bottom her speed is precisely two-thirds what it would have been if the slide had been frictionless. Calculate the coeffieicnt of kinetic friction between the slide and the child.

Also, I can't explain why, in those "rotor-rides" at the carnival where you're spun around fast enough to overcome static friction and not slide down, why you feel like you're being pressed against the wall but you're really not. Any help would be greatly appreciated.
 
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Welcome to the forums! :smile:

However in order to get help you need to SHOW US what progress you have made since we don't provide solutions we simply guide you along the way


ok first of all let's just assume that the child started to slide from rest

so then if there was no friction involved
\Delta K + \Delta U = 0

calculate the velocity (use variables only)
the height change you used here is somehow related to the length of the slide itself
Now that you have a velocity 2/3 of this velocity is the velocity you will use in the next part

assume ther was friction

\Delta K + \Delta U = W_{f} = F_{f} d = \mu F_{N} l

where L is the length of the slide
sub in what you have so far for the velocity (remember to square it!) you know the change in potential energy.

Draw a fre body body diagram of the child nad figure out the normal force and see waht cancels out. Your answer should have no need for the mass or the length of the slide.
 
For the second problem, I'll give you a hint: You get pressed against the wall right? What kind a reference frame are you in? What kind of a reference frame is a person on the ground in? What is the difference? (Sorry for making it look all so obvious...but you still got to reason it yourself mate).
 
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