Question

PROBLEM 2. A porter lifts a luggage of 15 kg from the
ground and puts it on his head 1.5 m above the ground.
Calculate the work done by him on the luggage. (NCERT)​

Answer 1

Explanation:

Roads are easy to build and maintain as compare to railways.

Constructions cost of roads is much lower that of railway lines.

Roads as compare to railways lines can negotiate higher gradients of slopes easily and as such can traverse mountains like Himalayas.

Answer 2

Answer:

The work done by porter on the luggage​ is 225 J

Explanation:

Given,

A porter lifts a luggage of mass = 15 kg from the ground.

It's on his head 1.5 m above the ground.

To find: The work done by him on the luggage​

Solution:

here, Force is due to the weight of the luggage.

i.e F = mg , where m = mass of luggage and g = accerleration due to gravity

or, F = 15 * 10 = 150 N

Work done can be given as:

W = F * s

where, F = force and s = displacement i.e 1.5 m

W = 150 * 1.5 = 225 J

Therefore, The work done by porter on the luggage​ is 225 J.