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A wheel starts from rest and rotates about its axis with constant angular acceleration. It completes 50 revolutions in the first 2 seconds. How many revolutions does it complete in the next 2 seconds?

1. 75
2. 100
3. 125
4. 150

Correct answer: 150

Solution

Since theta is proportional to t², total revs in 4 s = 50*(4/2)² = 200; revs in next 2 s = 200 - 50 = 150.

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