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The tires of a car make 88 revolutions as the car reduces its speed uniformly from 94.0 km/h to 64.0 km/h . the tires have a diameter of 0.88 m. what was the angular acceleration of the tires?

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Final answer:

The angular acceleration of the tires is -0.14 rad/s².

Step-by-step explanation:

To find the angular acceleration of the tires, we can use the formula:

angular acceleration = (final angular velocity - initial angular velocity) / time

The initial and final angular velocities can be calculated using the formula:

angular velocity = linear velocity / radius

Given that the tires have a diameter of 0.88 m, their radius would be 0.88/2 = 0.44 m.

Converting the speeds from km/h to m/s:

Initial linear velocity = 94.0 km/h × (1000 m/1 km) × (1 h/3600 s) = 26.11 m/s

Final linear velocity = 64.0 km/h × (1000 m/1 km) × (1 h/3600 s) = 17.78 m/s

Substituting the values into the formulas:

Initial angular velocity = 26.11 m/s / 0.44 m = 59.34 rad/s

Final angular velocity = 17.78 m/s / 0.44 m = 40.41 rad/s

Time = Number of revolutions × (2π × radius) / linear velocity

Number of revolutions = (time × linear velocity) / (2π × radius)

Given that the number of revolutions is 88:

Angular acceleration = (40.41 rad/s - 59.34 rad/s) / ((88 × 2π × 0.44 m) / 17.78 m/s) = -0.14 rad/s²

Therefore, the angular acceleration of the tires is -0.14 rad/s².

User Ahmad Nadeem
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