What is the initial speed of the ball as it rolls up an inclined ramp?

AI Thread Summary
The discussion focuses on determining the initial speed of a uniform solid ball rolling up a 15° inclined ramp. Participants clarify that the problem refers to linear speed rather than angular speed, as the ball rolls without slipping. It is suggested that conservation of energy is the most effective method for solving the problem, despite the possibility of using kinematics. The role of friction is noted, as it exerts torque on the ball, affecting angular momentum. Overall, the consensus is that the initial speed can be calculated using energy principles, emphasizing linear speed in the context of the problem.
bearhug
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A uniform solid ball rolls smoothly along a floor, then up a ramp inclined at 15.0°. It momentarily stops when it has rolled 1.50 m along the ramp.
(a) What was its initial speed?

First of all I'm assuming that the initial speed is the linear and not the angular speed is this right?

Originally I was using Li=Lf where L=Iw however that is with angular speed and not linear speed. Would this problem involve using kinematics at all? What's throwing me off is which speed it is referring to. Any help is appreciated.
 
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Sounds like a conservation of energy problem. I'm guessing it is asking for translational velocity
 
bearhug said:
First of all I'm assuming that the initial speed is the linear and not the angular speed is this right?
Since you are not given the ball's radius, all you can determine is the linear speed. (But since the ball rolls smoothly--without slipping--the linear and angular speeds are directly related.)
Originally I was using Li=Lf where L=Iw however that is with angular speed and not linear speed.
Angular momentum is not conserved here--friction exerts a torque on the ball as it rolls up the incline.
Would this problem involve using kinematics at all?
You certainly could solve this problem using kinematics (after figuring out the acceleration of the ball on the incline), but using conservation of energy will be easier.
 
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