Question

A body of mass 5kg is dropped to the ground from a height of 15 meters . The work done by the gravitational force is?

Answer 1

Answer:-

w = 750 J

Given :-

m = 5 kg

h = 15 m

g = 10 m/s²

To find :-

The work done by gravitational force.

Solution:-

The work done is equal to its gravitational potential energy.

Potential energy → The energy possess by a body due to height above the surface of earth.

→$W = P. e$

→$W = mgh$

• Where m is the mass of object.
• g is the gravitational force.
• h is the height above the surface of earth.

• Put the given values

→$W = 5 \times 10 \times 15$

→$W = 750 J$

hence,

The work done by gravitational force is 750 J.

Answer 2

$\bold {\huge {Your ~answer :-}}$

$\bf\huge\boxed{750\:J}$

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Explanation —

Given-

Mass of body(m) = 5 kg

Height from where object is dropped= 15 m

To find-

WD by Gravitational force on the body =?

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Whe know the Work energy theoram

change in kinetic energy= work done by body

Taking above 15 m from ground as a refrance frame

KEi + PEi = KEf + PEf

Here i = initial, f = final

⇒KEf - KEi = - PEf + PEf

PEf = 0 becoz h is zero

⇒Work done = 0 + mgh

⇒Work done = (5 ×10 × 15)

⇒Work done = 750

∴Work done is 750 J