Question

A small, solid cylinder with mass = 20 kg and radius = 0.10 m starts from rest and rotates without friction about a fixed axis through its center of mass. A string is wrapped around the circumference of the cylinder and pulled using a constant force F. The resulting angular acceleration of the cylinder is 5.0 rad/s2. What length of string has unwound after 4.0 s, in meters? (The moment of inertia of the cylinder is 1 half M R squared.)

Answer 1

Step-by-step explanation:

angular acceleration α = 5 rad /s ²

θ = 1/2 α t² , θ is angle of rotation , t is time .

= .5 x 5 x 4²

= 40 rad .

θ = l / r , θ is angle formed , l is length unwound , r is radius o wheel .

l = θ x r

= 40 x .1

= 4 m .