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A body rotating with an angular speed of 600 rpm is uniformly accelerated to 1800 rpm in 10 sec. The number of rotations made in the process is _____.

1. 100
2. 150
3. 200
4. 300

Correct answer: 200

Solution

The body undergoes a uniform angular acceleration, which allows us to use the formula for angular displacement during acceleration. By calculating the average angular speed and multiplying it by the time, we find that the total number of rotations made is 200.

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