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A wheel initially at rest is subjected to a uniform angular acceleration about its axis. In the first 2 s it rotates through an angle 1 and in the next 2 s it rotates through an angle 2. The ratio 2 1 is .
(2) 3
Starting from rest: = 12 t2
First 2 s: 1= 12 (2)2=2
First 4 s: 1+ 2= 12 (4)2=8
2=8 -2 =6
2 1= 6 2 =3
(Angles in equal successive intervals from rest are in the ratio 1 : 3 : 5 …)
Answer: (2)
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