The `50 N` collar starts from rest at `A` and is lifted with a constant speed of `0.6 m//s` along the smooth rod. Determine the power developed by the force `F` at the instant shown.
.

Options

A. `20 W`
B. `30 W`
C. `10 W`
D. `40 W`

Answer

`(2)`

Explanation

Since the collar is lifted with a constant speed
`T cos theta - mg = 0 Rightarrow T cos theta = mg = 5 xx 10`
Now, ` p = vec F . vec v = T cos theta xx v, Here T = F`
` P = 50 xx v xx 0.6 = 30 W`