Question 3

A contractor plans to install two slides for the children to play in a park. For the children below the age of 5 years, she prefers to have a slide whose top is at a height of 1.5 m, andis inclined at an angle of 30° to the ground, whereas for elder children, she wants to have a steep slide at a height of 3m, and inclined at an angle of 60° to the ground. What should be the length of the slide in each case?

Answer

(i) For Children below age of 5 years

Height of slide = 1.5 m

Angle of inclination of slide = 30^{o}

(ii) For Children below age of 5 years

Height of slide = 3m

Angle of inclination of slide = 60^{o}

Draw figure for both cases:

In right Δ ABC, we have

Sin 30^{o} = AB / AC => 1/ 2 = 1.5 /AC [ sin30^{o} =1/2]

AC = 3m

In right Δ DEF, we have

Sin 60^{o} = DE /DF =>

DF =

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