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A bicyclist starting at rest produces a constant angular acceleration of 1.70 rad/s² for wheels that are 37.5 cm in diameter. What is the angular speed of the wheels (in rad/s) when the bicyclist reaches 12.0 m/s?

User Bonono
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1 Answer

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Final answer:

The angular speed of the wheels is approximately 75.30 rad/s when the bicyclist reaches 12.0 m/s

Step-by-step explanation:

To determine the angular speed of the wheels when the bicyclist reaches 12.0 m/s, we can use the formula:

ω = ω0 + αt

Where:



  • ω is the final angular speed
  • ω0 is the initial angular speed, which is 0 since the bicyclist starts at rest
  • α is the constant angular acceleration, which is given as 1.70 rad/s²
  • t is the time taken to reach the final speed

We can calculate t using the formula:

v = v0 + at

Where:



  • v is the final linear speed, which is 12.0 m/s
  • v0 is the initial linear speed, which is 0 since the bicyclist starts at rest
  • a is the linear acceleration, which can be calculated using the formula a = αr, where r is the radius of the wheel


Given that the diameter of the wheel is 37.5 cm, the radius can be calculated as 37.5 cm ÷ 2 = 18.75 cm = 0.1875 m.

Plugging in the values, we get:

t = (v - v0) / a = (12.0 m/s - 0 m/s) / (1.70 rad/s² * 0.1875 m) ≈ 44.29 s

Now we can calculate the final angular speed:

ω = ω0 + αt = 0 + 1.70 rad/s² * 44.29 s ≈ 75.30 rad/s

User Codigomonstruo
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