Answers

2016-02-19T09:07:15+05:30
See diagram for details.
Let AB be flagpole.
BC be shadow at 60°
BD be shadow at θ°

To find: Angle θ°

BD = 3BC (as per question) ...(1)

Therefore,
=> tan 60° = AB/BC
=> √3 = AB/BC
=> AB = BC√3 ...(2)

=> tan θ° = AB/BD
= BC√3/3BC (From 1 and 2)
= √3/3
= 1/√3

∴ tan θ° = 1/√3
∴ tan θ° = tan 30°
∴ θ° = 30°

Therefore the angle at the instant is 30°.
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