# Physics??

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A car is traveling at a speed of 62 on a freeway.
If its tires have diameter 24.0 and are rolling without sliding or slipping, what is their angular velocity?

• Physics?? -

You must provide dimensions along with your numbers. 62 what? mph? 24.0 what? inches?

A nonslipping tire's speed (and that of the car) is
V = R*w
where w is the angular velocity in radians per second.

You do the numbers.

The length and speed dimensions must be consistent. (feet and feet/s or meters and meters/s)

• Physics?? -

its 62 mi/h and 24.0in

• Physics?? -

do i do 2pi/ 62 first?

• Physics?? -

w = V/R

V = 62 mi/h = 90.93 ft/s
R = 24 in = 0.6667 ft

Now that you have consistent dimensions for V and R,

w = 90.93/0.6667 = 136.4 rad/s

• Physics?? -

i got the anwser wrong

• Physics?? -

It looks right to me. Sometimes the online problem writers get it wrong, and sometimes it's me. The equation is correct.

• Physics?? -

But cant u jus convert the diameter to meter nd d v to m/s. Besides that 24inc was the diameter which should hav been divided by two to get the radius