Question

A porter having a 10kg load on his head moves 200m on a levelled platform. The work done against gravitational force will be (g = 10 m/s² )Required to answer. Single choice.



20 KJ

200 J

0 J

2 KJ​

Answer 1

Answer:

0 J

Explanation:

Given :

A porter having a 10kg load on his head moves 200m on a levelled platform.

To find :

the work done against the gravitational force

Solution :

Gravitational force :

• It is the force which attracts any two objects which have mass.

• It is the attractive force
• Gravitational force between two objects is given by,

        $\boxed{\sf F=\dfrac{Gm_1m_2}{d^2}}$

where

G denotes gravitational constant

m₁ , m₂ are the masses of two objects

d denotes the distance of separation between the objects

➙ The direction of acceleration due to gravity is always vertically downwards.

➙ So, the direction against the gravitational force is vertically upwards.

➙ The porter moved 200 m on a levelled platform. That means his displacement is in horizontal direction.

➙ There is no displacement along vertically upward direction.

➙ Work done is the product of force and displacement.

    W = F × d

➙ As there is no displacement, work done equals zero.

Hence, the work done against gravitational force will be 0 J