Please help so confused

Question

a washing machine drum rotates at a speed of 1,500 rpm during the spin cycle. What is the angular velocity of the drum in radians per second?

a) 25/2pi radians per second

b) 50pi radians per second

c) 45000pi radians per second 

d) 180000pi radians per second 

Answer 1

1,500 rpm, or revolutions per minute, is how many revolutions per second?

 

1,500 rev./min  *  1 min. / 60 sec   =  25 rev / sec.

 

There are 2*pi radians in a revolution, so

 

25 rev / sec  *  2*pi radians / rev   =   50*pi radians / sec