A cord is wrapped around each of the two 20-kg disks. They are released from res
ID: 1998045 • Letter: A
Question
A cord is wrapped around each of the two 20-kg disks. They are released from rest. Suppose that r = 76 nun Neglect the mass of the cord. (Figure 1) Determine the angular acceleration of disk A. measured clockwise. Express your answer using three significant figures. Enter positive value if the angular acceleration is clockwise and negative value if the angular acceleration is counterclockwise. Determine the angular acceleration of disk B measured clockwise. Express your answer using three significant figures. Enter positive value if the angular acceleration is clockwise and negative value if the angular acceleration is counterclockwise Determine the tension in the cord C. Express your answer to three significant figures and include the appropriate units.Explanation / Answer
Angular acceleration alpha = T*0.076/(0.5×20*0.076^2) = 1.316T
Also mg - T = m alpha R
T = m*(g-alphaR)
now alpha = 20*(9.8 -0.076 alpha)*1.316
alpha = 196*1.316 - 2alpha
alpha = 196*1.316/3
= 8.60 rad/s^2
B) alpha = -8.60 rad/s^2
C) Tension = alpha/1.316
= 8.6/1.316
= 6.53 N