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Rotational Mechanics — Physics STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 SciencePhysicsRotational Mechanics3 Marks
Question
A wheel starting from rest is uniformly accelerated at $4 \text{ rad/-s}^2$ for $10$ seconds.It is allowed to rotate uniformly for the next $10$ seconds and is finally brought to rest in the next $10$ seconds. Find the total angle rotated by the wheel.
✓

Answer

Area under the curve will decide the total angle rotated
$\therefore$ Maximum angular velocity $= 4 \times 10 = 40 \text{ rad/-s}$
Therefore, area under the curve $=\frac{1}2{}\times10\times40+40\times10+\frac{1}{2}\times40\times10$
$=800\text{ rad}$
$\therefore$ Total angle rotated $= 800\ \text{ rad}.$
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