Mathematics · 2018
JEE Main · 16 April 2018, Shift 1 · Q89
A man on the top of a vertical tower observes a car moving at a uniform speed towards the tower on a horizontal road. If it takes 18 min. for the…
A man on the top of a vertical tower observes a car moving at a uniform speed towards the tower on a horizontal road. If it takes $\displaystyle 18$ min. for the angle of depression of the car to change from $\displaystyle 30$° to $\displaystyle 45$°; then after this, the time taken (in min.) by the car to reach the foot of the tower, is :
Official answer
(1)
$\displaystyle 9(1+\sqrt{3})$
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JEE Main 2018 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.