Physics-
General
Easy
Question
A loop of radius 3 meter and weighs 150 kg. It rolls along a horizontal floor so that its centre of mass has a speed of 15 cm/sec. How much work has to be done to stop it –
- 3.375 J
- 7.375 J
- 5.375 J
- 9.375 J
The correct answer is: 3.375 J
Required work = Total K.E.
= 
mv2 
= 
= × 150× (0.15)2 (1+ 1) = 3.375 J
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