Block A and Block B are hanging from a two-radius pulley, as shown. Block A is s
ID: 2147678 • Letter: B
Question
Block A and Block B are hanging from a two-radius pulley, as shown. Block A is suspended by a massless cord that is wrapped around the pulley
Explanation / Answer
the acceleration of the blocks : a = F/(m + kM) ----> m = mass of the translational object = 4 + 2 = 6 kg ----> M = mass of the rotational object = mass of pulley = 0.8 kg F = force = weight of the hanging block = 2 * 9.8 = 19.6 N k for a disk = 1/2 --> a = 19.6/(6 + (1/2)*0.8) = 3.06 m/s^2 v^2 = u^2 + 2 * a * d = 0 + 2 * 3.06 * 2.5 = 15.3 v = sqrt (15.3) = 3.91 m/s b) the angular velocity of the pulley at this time : ? = v/r = 3.91/0.12 = 32.58 rad/s