Question

1. Find the linear velocity of a point rotating at 30 revolutions per second on a circle of radius 4 centimeters.

2. A pulley is driven by a belt moving at a speed of 29.3 feet per second. If the pulley is 8 inches in diameter, approximate the angular velocity of the pulley in revolutions per second.

Answer 1

for #1, start by finding the perimeter of the circle

Answer 2

From that you can figure the linear/tangent velocity from distance (circumference) over time of the period

Answer 3

The angular velocity is in degrees of the circle per time

Answer 4

the tangent velocity and the angle velocity are related, try that

Answer 5

that makes absolutely no sense to me

Answer 6

There are no angles mentioned in either problem

Answer 7

eh... solved the problem somehow I forgot how though. ahah

Answer 8

1revolution travels 1 circumference, since you travel forward on the outer part of a wheel.

30 revolutions a second travels a linear speed of 30 circumferences a second.

this can be worked backwards as well if we know the linear speed (speed of a belt) ...