JEE MainPhysicsRotational MotionNumerical+4 / −1
A body of mass m = 10 kg is attached to one end of a wire of length 0.3 m. The maximum angular speed (in rad s–1) with which it can be rotated about its other end in space station is : (Breaking stress of wire = 4.8 × 107 Nm–2 and area of cross-section of the wire = 10–2 cm2) is:
Numerical answer
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Correct answer: 4
- Given data
- Mass of body:
- Length of wire:
- Breaking stress of wire:
- Area of cross-section:
- Convert area into SI units
Since,
Therefore,
- Maximum tension in the wire
Breaking stress is
So,
- Condition for circular motion in space station
Since the body is rotated in a space station, effectively there is no gravity affecting the rotation. Hence the wire tension alone provides the centripetal force:
At maximum angular speed, tension reaches breaking value:
Thus,
- Final answer
The maximum angular speed is:
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