If a wheel of diameter 28 inches moves at a speed of 100 kilometers per hour, how many radians per second does it revolve?

1 Answer
Feb 13, 2018

78.12 radians per second

Explanation:

As diameter is 28, circumference of the wheel is 28pi inches or

28pixx2.54=71.12pi cm.

As it travels 100xx1000xx100 cm. in an hour,

wheel is taking (100xx1000xx100)/(71.12pi) revolutions in an hour or in 3600 seconds

i.e. (100xx1000xx100)/(71.12pixx3600) revolutions per second

or (100xx1000xx100)/(71.12pixx3600)xx2pi radians per second

i.e. (100xx1000xx100)/(71.12xx1800)~=78.12 radians per second