a wheel is rolling along with a speed of 20 meters per second. if the wheel has a diameter of 52 centimeters, what is the angular speed in revolutions per minute?
2007-03-20 13:19:16 · 1 answers · asked by argentina_mandy20 1 in Science & Mathematics ➔ Physics
v =wr; where v = tangential velocity, w = angular velocity, and r = radius of the wheel.
The tangential velocity is the "speed" of the axle moving at 20 m/sec. Thus, v = 20 m/sec = wr = w .26 m; so that w = 20/.26 revolutions per second, which is about 80 rps.
Lesson learned: the rotation of the axle around the point of contact on the ground is the same as the rotation of the point on the ground around the axle. Clearly the axle doesn't rotate around the point on the ground, but in an instant, some small delta of time, they are equivalent. And doing the axle around the point on the ground is way easier than vice versa.
2007-03-20 13:31:44 · answer #1 · answered by oldprof 7 · 1⤊ 0⤋