Question
Question: A cord of negligible mass is wound round the rim of a flywheel of mass 20 kg and radius 20 cm. A ste...
A cord of negligible mass is wound round the rim of a flywheel of mass 20 kg and radius 20 cm. A steady pull of 25 N is applied on the cord. The work done by the pull when 2 m of the cord is unwound
A
20 J
B
25 J
C
45 J
D
50 J
Answer
50 J
Explanation
Solution
Word done by the pull unwinding 2 m of the cord.
W = 25 N × 2 m = 50 J