An Object of Mass,m,is Placed in an Arc of a Circle

question 26

Multiple Choice

An object of mass,m,is placed in an arc of a circle of radius,r.The coefficient of kinetic friction between the object and the surface of the arc is $\mu$ _k.What is the work done by friction in going from P₁ and P₂?

• A)-\(\mu\)_kmg r (cos(\(\theta\)₂)-cos(\(\theta\)₁))
• B)-\(\mu\)_kmg r (sin(\(\theta\)₂)-sin(\(\theta\)₁))
• C)-\(\mu\)_kmg r cos(\(\theta\)₂)sin\(\theta\)₁)
• D)-\(\mu\)_kmg r sin(\(\theta\)₂)cos(\(\theta\)₁)
• E)none of the above