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?
(i) For Children below age of 5 years
Height of slide = 1.5 m
Angle of inclination of slide = 30o
(ii) For Children below age of 5 years
Height of slide = 3m
Angle of inclination of slide = 60o
Draw figure for both cases:
In right Δ ABC, we have
Sin 30o = AB / AC => 1/ 2 = 1.5 /AC [ sin30o =1/2]
AC = 3m
In right Δ DEF, we have
Sin 60o = DE /DF =>
DF =
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