In a home laundry drier, a cylindrical tub containing wet clothes rotates steadily about a horizontal axis, as in Figure P7.63. The clothes are made to tumble so that they will dry uniformly. The rate of rotation of the smooth-walled tub is chosen so that a small piece of cloth loses contact with the tub when the cloth is at an angle of 68.0° above the horizontal. If the radius of the tub is 0.340 m, what rate of revolution is needed?
2006-11-03 05:40:07 · 1 answers · asked by RunmanJr2 2 in Science & Mathematics ➔ Physics
The rotation rate is such that the centripetal acceleration equals the component of the downward acceleration of gravity that acts normal to the cylinder's wall at 68 deg. Thus, solve the following for w (rotation rate):
w^2*r = g*sin(68).
Thus w = SQRT(g*sin(68)/0.34) = 5.17 radians/sec = 49.38 rev/min.
2006-11-04 00:50:21 · answer #1 · answered by kirchwey 7 · 0⤊ 1⤋