1. The problem statement, all variables and given/known data A ball of mass 2.60 kg and radius 0.120 m is released from rest on a plane inclined at an angle θ = 36.0° with respect to the horizontal. How fast is the ball moving (in m/s) after it has rolled a distance d=1.90 m? Assume that the ball rolls without slipping, and that its moment of inertia about its center of mass is 1.40×10-2 kg·m2. 2. Relevant equations Given: I = 1.40×10-2 kg·m2. Linear Acceleration = r*ω KE = 0.5Iω^2 PE = MGH μ=Tanθ 3. The attempt at a solution Using the hypotenuse and the angle, I solved that the Height from the ground should be 1.12 m Then, I decided to use energy equations to go about this. ΔKE = 1/2*I*ω(final)^2 - 1/2*I*ω(initial)^2 Since it's not moving initially ΔKE = 1/2*I*ω^2 Then Since I wanted to get linear acceleration I solved a=rω for omega and got ω=a/r I plugged that in to get an equation of ΔKE = 1/2*I*(a/r)^2. Although I've just realized my question prompts for a velocity not an acceleration, so I guess I can go back to ΔKE = 1/2*I*ω^2 Then with ΔKE + ΔPE + ΔEThermal = 0 ΔPE = MGH final - MGH initial so 0 - MGH 1/2*I*ω^2 - MGH + ΔEThermal = 0 I know that μ should be equal to Tanθ after solving MGsinθ = μ *MGcosθ Here's where I've kinda blanked out... I can't seem to figure out what to put for friction. As I know that exists because the ball is not slipping down the ramp Help would be very much appreciated. Am I even headed in the correct direction? Edit: And I'm realizing now that this path leads me to an Imaginary number... so I've missed it somewhere.