"A car is traveling at 100 km/h and the tire of the car has a radius of 36cm. Find the number of revolutions per second."
The Attempt at a Solution
100 km/h * (10,000,000 cm/km) * (1h/3600 secs) = 2777.77777778 cm/s is the speed of the car.
Θ = a/r
Θ = (2777.78) / (36)
Θ = 77.16
To find number of revolutions, we must divide by 2pi.
77.16/2pi = 12.28 revolutions/sec. That is the correct answer.
a) I did not get that on the quiz because I do not understand the mechanics behind the operation. Can anyone walk me through each calculation and state why that step is done?
b) And why is 2777.78 cm/s equal to the arc length? Isn't arc length a distance? I thought 2778.78 cm/s was a velocity measurement.