Question

С какой частотой вращается колесо мотоцикла, движущегося со скоростью 72 км/ч, если диаметр колеса 90 см?

Answer 1

T=2*pi*R/V=6,28*0,9/20=0,283 c
v=1/T=1/0,283=3,53 Гц

Answer 2

Calculation of Wheel Rotation Frequency

To calculate the rotation frequency of a motorcycle wheel, we can use the formula:

Rotation frequency (in Hz) = Speed (in m/s) / Circumference of the wheel (in meters)

First, let's convert the given speed from kilometers per hour (km/h) to meters per second (m/s):

Speed = 72 km/h = 72 * (1000/3600) m/s = 20 m/s.

Next, we need to calculate the circumference of the wheel using the given diameter:

Circumference = π * Diameter

Given that the diameter of the wheel is 90 cm, we can calculate the circumference as follows:

Circumference = π * 90 cm = π * 0.9 m = 2.8274 m.

Now, we can calculate the rotation frequency:

Rotation frequency = Speed / Circumference = 20 m/s / 2.8274 m ≈ 7.08 Hz.

Therefore, the wheel of the motorcycle, moving at a speed of 72 km/h, rotates at a frequency of approximately 7.08 Hz.

Please note that the above calculation assumes that the motorcycle wheel is rolling without any slipping or skidding.

Let me know if there's anything else I can help you with!