Compare the power at which each of the following is moving upwards against the force of gravity? (given g = 10 m s–2) (i) a butterfly of mass 1.0 g that flies upward at a rate of 0.5 m s–1. (ii) a 250 g squirrel climbing up on a tree at a rate of 0.5 m s–1.
ScienceClass 9CBSEAnswered 27 Mar 2026
Answer
Soln:
- Butterfly force= mg=1/100 power=f×s÷t. {s÷t=velocity} power=1÷100×.5 power=1÷200W
- squirrel force=mg=25 power=25×.5 power=12.5W
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