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 upward at a rate of `0.5 m//s` (ii) a 250 g squirrel climbing up on a tree at a rate of `0.5 m//s`.

Explanation

(i) Given, mass of butterfly `=1.0g=(1)/(1000)kg." "[:'1kg=1000g]`
`g=10ms^(-2)and speed=0.5ms^(-1)`
`"Power"="Force"xx"Speed"" "[:'"Force"(f)=mg]`
P=mgv
`P=(1)/(1000)=xx10xx0.5`
`rArrP=(1)/(200)W`
(ii) Given, mass of squirrel `=250g=(250)/(1000)kg" "[:'1kg=1000g]`
and speed `=0.5ms^(-1)`
`:."Power"="Force"xx"speed"" "["Force",F=mg]`
p=mgxxv
`P=(250)/(10000)xx10xx0.5=(250)/(200)W`
`:.P=(250)/(200)W`
Therefore, squirrel has more power than butterfly.