Question

A bucket of mass `4//3` is tied to a string and is lowered at a constant acceleration of `g//4`. The magnitude of work done (in joule ) by the string in lowering the bucket by `10 cm` would be `:`

Answer 1

Here, `m=(4)/(3) kg, a =(g)/(a) , ` downwards.
If `T` is tension in the string, then
`T=m(g-a)=(4)/(3)(g-(g)/(4))=(4)/(3).(3g)/(4)=g`
Magnitude of work done by string,
`W=Txxs=gxx(10)/(100)=10 xx (10)/(100)=1J`