Same chapter4 marksDifficulty: Hard
An aeroplane flying horizontally at a height of 3000 m is observed at an angle of elevation of 60°. After 15 seconds the angle is 30°. Find the speed of the aeroplane in km/h.
Heights and Distances
4 marksDifficulty: Hard
A boy 1.5 m tall stands 20 m from a tree and finds the angle of elevation of its top to be 30°. Find the height of the tree.
Original Khojo Papers practice question — not from a past board paper.
Answer
About 13.05 m
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The height above the boy's eye level is 20 tan 30° = 20/√3 ≈ 11.55 m. Adding the boy's own height gives about 13.05 m.
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From the same topic and chapter, at a similar level.
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Heights and Distances
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Same chapter3 marksDifficulty: Easy
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Heights and Distances