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Question
The following figure shows a small wheel fixed coaxially on a bigger one of double the radius. The system rotates about the common axis. The strings supporting A and B do not slip on the wheels. If x and y be the distance travelled by A and B in the same time interval, then _________ .
Options
x = 2y
x = y
y = 2x
None of these
Solution
y = 2x
It is given that angular velocity is same for both the wheels.
Therefore, we have
vA = \[\omega\] R
vB =\[\omega\]2R
x = vAt = \[\omega\]Rt ............(1)
y = vBt = \[\omega\](2R)t ..............(2)
From equations (1) and (2), we get
y = 2x
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