Question

25. A vertical electrical pole of 20 m. long casts a shadow of 12 m. long on the ground. At the
same time a building casts the shadow of 48 m long on the ground. Determine the height of
the building​

Answer 1

Given:

A vertical electrical pole of 20 m. long casts a shadow of 12 m.

To find:

The height of the other building whose shadow is 48 m long.

Solution:

1) At the same time if two or more objects cast the shadow by the Sun and at that moment the sun is fixed at a point so the ratio of the height of the object and height of the shadow is always proportional to the other one.

2) Height of pole = 20 m.

Height of shadow of pole  = 12m.

Let the height of building = X m

Height of the shadow of the building = 48 m.

as per the rule,

• 20/12 = X/48

• X = 20/12 ×48

• X = 20×4

• X = 80m.

The height of the building is 80 m.