Question

Calculate the work done in lifting a 50 kg box through a vertical height of 5m (assume g= 10m/s2)

a)2500 J

b)2000 J

c)250 J

d)500 J

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Answer 1

Answer:

Mass of the box = 50 kg

Height at which the object is held = 5 m

Gravitational force = 10m/s²

∴ Work done = mass x height x gravity

= 50 x 5 x 10

= 2500 J

The required option is Option A : 2500 J.

Knowledge Bytes:

→ Work done is measured as the product of the force and the displacement caused by the force.

→ We can measure the work done by an object when held vertically upwards by multiplying the mass of the object, the height at which the object is held and the gravitational force acting on it.

That is, Work [W] = mgh where,

m =mass of the object

g = gravitational force

h = height at which the object is held

Answer 2

Answer:

250 J

Explanation: