HARD
JEE Main
IMPORTANT
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A man is walking towards a vertical pillar in a straight path, at a uniform speed. At a certain point A on the path, he observes that the angle of elevation of the top of the pillar is 30°.  After walking for 10 minutes from A in the same direction, at a point B, he observes that the angle of elevation of the top of the pillar is 60° . Then the time taken (in minutes) by him, from B to reach the pillar, is

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Important Questions on Heights and Distances

MEDIUM
JEE Main
IMPORTANT
If the angles of elevation of the top of a tower from three collinear points A, B and C on a line leading to the foot of the tower are 30°, 45° and 60° respectively, then the ratio AB:BC, is
MEDIUM
JEE Main
IMPORTANT
Let 10 vertical poles standing at equal distances on a straight line, subtend the same angle of elevation α at a point O on this line and all the poles are on the same side of O. If the height of the longest pole is h and the distance of the foot of the smallest pole from O is a; then the distance between two consecutive poles, is
MEDIUM
JEE Main
IMPORTANT
A bird is sitting on the top of a vertical pole 20 m high and its elevation from a point O on the ground is 45°. It flies off horizontally straight away from the point O. After one second, the elevation of the bird from O is reduced to 30°. Then the speed (in m/s) of the bird is 
EASY
JEE Main
IMPORTANT
Let AB and PQ be two vertical poles, 160m apart from each other. Let C be the middle point of B and Q, which are feet of these two poles. Let π8 and θ be the angles of elevation from C to P and A, respectively. If the height of pole PQ is twice the height of pole AB, then tan2θ is equal to
EASY
JEE Main
IMPORTANT
From the base of a pole of height 20 meter, the angle of elevation of the top of a tower is 60°. The pole subtends an angle 30° at the top of the tower. Then the height of the tower is:
MEDIUM
JEE Main
IMPORTANT
A tower PQ stands on a horizontal ground with base Q on the ground. The point R divides the tower in two parts such that QR=15m. If from a point A on the ground the angle of elevation of R is 60° and the part PR of the tower subtends an angle of 15° at A, then the height of the tower is 
MEDIUM
JEE Main
IMPORTANT
Let a vertical tower AB of height 2h stands on a horizontal ground. Let from a point P on the ground a man can see upto height h of the tower with an angle of elevation 2α. When from P, he moves a distance d in the direction of AP, he can see the top B of the tower with an angle of elevation α. If d=7h, then tanα is equal to
HARD
JEE Main
IMPORTANT
The angle of elevation of the top P of a vertical tower PQ of height 10 from a point A on the horizontal ground is 45°. Let R be a point on AQ and from a point B, vertically above R, the angle of elevation of P is 60°. If BAQ=30°,AB=d and the area of the trapezium PQRB is α, then the ordered pair d,α is