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a bicycle wheel with a radius of 0.30 m starts from rest and accelerates at a rate of 4.5 rad/s² for 11 s. how many revolutions did it make?

User Gurmeet
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Final answer:

To find the number of revolutions a bicycle wheel made after accelerating from rest for 11 seconds with an angular acceleration of 4.5 rad/s², we used rotational motion equations to calculate the angular displacement and then divided by 2π to convert to revolutions, resulting in approximately 43.36 revolutions.

Step-by-step explanation:

To calculate how many revolutions the bicycle wheel made, we need to use equations for rotational motion. The given values are the initial angular velocity (ω0 = 0 rad/s, since it starts from rest), the angular acceleration (alpha = 4.5 rad/s²), and the time interval (t = 11 s).

The equation for the angular displacement (theta) in radians after a time t under constant angular acceleration is:

theta = ω0t + 0.5*alpha*t²

Plugging in the given values:

theta = (0 rad/s)(11 s) + 0.5*(4.5 rad/s²)(11 s)²

theta = 0 + 0.5*4.5*121

theta = 272.25 rad

Since one revolution is 2π radians, we divide the angular displacement by 2π to get the number of revolutions (N):

N = theta / (2π)

N = 272.25 rad / (2π)

N = 43.36 revolutions

The bicycle wheel made approximately 43.36 revolutions during the 11 seconds it was accelerating.

User AlexStack
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