Question

4. a boy of height 150 cm is walking
away from the base of a lamp post at
a speed of 1.6 m/s .if the lamp is 4.5
m above the ground. length of his
shadow after 5 sec
10cm
6 cm
O 4 cm
none of these​

Answer 1

Answer:

if you want to keep this short, none of these

Step-by-step explanation:

Given the height of boy =150 cm. = 1.5m

lamp post = 4.5m

girl is moving with velocity (V) = 1.6m/s away  

from lamp post  

∴ distance travelled by girl after 5 second is

x= 1.6 × 5 = 8m

By concept of Similar triangles  

1.5m/4.5m

=  y/(x+y)  

⇒y(8+y)=3.6y