A wheel which is initially at rest is subjected to a constant angular acceleration about its axis. It rotates through an angle of `15^@` in time `t` sec. Then how much it rotates in the next `2t` sec

A wheel which is initially at rest is subjected to a constant angular

1.	A wheel which is initially at rest is subjected to a constant angular acceleration about its axis. It rotates through an angle of `15^@` in time `t` sec. Then how much it rotates in the next `2t` sec
Answer» If angular acceleration is constant, we have `theta=omega_(0)t+1/2alphat^(2)rArr15^(@)=0+1/2 alphat^(2)rArr15^(@)=1/2 alphat^(2)....(1)` For the second condition (time `3 t sec`) `theta_(1)=1/2alpha(3t)^(2)......(2)` So, `Deltatheta=theta_(1)-theta_(2)=120^(@)`

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A wheel which is initially at rest is subjected to a constant angular acceleration about its axis. It rotates through an angle of `15^@` in time `t` sec. Then how much it rotates in the next `2t` sec

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