Question

Two buildings of height 40 m and 100 m are perpendicular to ground. If the length of shadow of smaller building is 60m then what will be the shadow of bigger building at same time? ​

Answer 1

Answer:

40/60=100/x

60×100=40x

60×100/40=x= 150M

Answer 2

given two building and length of the shadow of one of them at a particular time of the day, find the shadow the other at the time.

Explanation:

1. at a particular time of the day the position of the sun with respect to both the buildings will be same as it is given that both the buildings are perpendicular to the ground.
2. hence, let $\theta$ be the angle that sunlight makes with the top of both buildings then , $tan\theta=\frac{shadow_A}{length_A} =\frac{shadow_B}{length_B}$      
3. now we have, $length_A=40m,\ length_B=100m,\ shadow_A=60m, \ shadow_B=?$                             from $tan\theta$  we get,                          

        $\frac{shadow_A}{length_A} =\frac{shadow_B}{length_B} \\\\\frac{60}{40} =\frac{shadow_B}{100} \\\\shadow_B=150$    ----->ANSWER