Topic :-

Work, Power and Energy

Given :-

A stone of mass 10kg and specific gravity 3 is raised from the bed of a lake to height of 6m in water in 9.8s.

To Find :-

Power exerted in performing given statements.

Formulae Used :-

Solution :-

Calculating loss of mass in water,

Specific Gravity = 3

Mass = 10 kg

Mass of stone in water = Original Mass - Lost Mass

Mass of stone in water =

Mass of stone in water =

Force = Mg

Work Done = Force × Height Displaced

Height displaced = 6 metres

Time = 9.8 seconds

Power = 20 × 2 W

Power = 4 × 10 W

Answer :-

So, value of blank is 4.

Verified answer

Explanation:

Formula for potential energy:

The formula for potential energy depends on the force acting on the two objects. m×g×h.

The Potential Energy comes under Work Done.

Mass = 10kg

Gravity = 3nm^2÷kg^2 from bed

Height = 6m

Therefore the Work Done = m×g×h

= 10×3×6

= 180

Therefore the answer is 180 joules.