MEDIUM
JEE Main
IMPORTANT
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The angle of elevation of the top of a tower from a point A due north of it is α and from a point B at a distance of 9 units due west of A is cos-1313. If the distance of the point B from the tower is 15 units, then cotα is equal to

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Important Questions on Heights and Distances

EASY
JEE Main
IMPORTANT
A vertical pole fixed to the horizontal ground is divided in the ratio 3: 7 by a mark on it with lower part shorter than the upper part. If the two parts subtend equal angles at a point on the ground 18 m away from the base of the pole, then the height of the pole (in meters) is :
MEDIUM
JEE Main
IMPORTANT
A spherical gas balloon of radius 16 meter subtends an angle 60° at the eye of the observer A while the angle of elevation of its center from the eye of A is 75°. Then the height (in meter) of the top most point of the balloon from the level of the observer's eye is :
HARD
JEE Main
IMPORTANT
A pole stands vertically inside a triangular park ABC. Let the angle of elevation of the top of the pole from each corner of the park be π3. If the radius of the circumcircle of ΔABC is 2, then the height of the pole is equal to :
MEDIUM
JEE Main
IMPORTANT
Two vertical poles are 150 m apart and the height of one is three times that of the other. If from the middle point of the line joining their feet, an observer finds the angles of elevation of their tops to be complementary, then the height of the shorter pole (in meters) is:
MEDIUM
JEE Main
IMPORTANT
The angle of elevation of a jet plane from a point A on the ground is 60°. After a flight of 20 seconds at the speed of 432 km/hour, the angle of elevation changes to 30°. If the jet plane is flying at a constant height, then its height is:
MEDIUM
JEE Main
IMPORTANT
A man is observing, from the top of a tower, a boat speeding towards the tower from a certain point A, with uniform speed. At that point, angle of depression of the boat with the man's eye is 30° (Ignore man's height). After sailing for 20 seconds, towards the base of the tower (which is at the level of water), the boat has reached a point B, where the angle of depression is 45°. Then the time taken (in seconds) by the boat from B to reach the base of the tower is :
HARD
JEE Main
IMPORTANT
The angle of elevation of a cloud C from a point P, 200 m above a still lake is 30o. If the angle of depression of the image of C in the lake from the point P is 60o, then PC (in m) is equal to
HARD
JEE Main
IMPORTANT
The angle of elevation of the top of a hill from a point on the horizontal plane passing through the foot of the hill is found to be 45°. After walking a distance of 80 meters towards the top, up a slope inclined at angle of 30° to the horizontal plane the angle of elevation of the top of the hill becomes 75°. Then the height of the hill (in meters) is _____.