MEDIUM
10th CBSE
IMPORTANT
Earn 100

As observed from the top of lighthouse, 100 m high above sea-level, the angle of depression of a ship sailing directly towards it, changes from 30° to 60°. Determine the distance travelled by the ship in m during the period of observation corrected to two decimal places.
(3=1.732)

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Important Questions on Heights & Distances

MEDIUM
10th CBSE
IMPORTANT
New Mathematics for Class X>Chapter 9 - Heights & Distances>REVISION EXERCISE>Q 2
An aeroplane flying horizontally 1 km above the ground is observed at an elevation of 60°. After a flight of 10 seconds, its angle of elevation is observed to be 30° from the same point on the ground. Find the speed of the aero plane in km/h corrected to one decimal place.
 
MEDIUM
10th CBSE
IMPORTANT
New Mathematics for Class X>Chapter 9 - Heights & Distances>REVISION EXERCISE>Q 3
An aeroplane is flying at a height of 2500 m above the ground. From a point on the ground the angle of elevation of this aero plane was found to be 60°. If after 15 seconds of horizontal flight, the angle of elevation changes to 30°, and the speed of the aero plane is k39 m/s. Find k.
MEDIUM
10th CBSE
IMPORTANT
New Mathematics for Class X>Chapter 9 - Heights & Distances>REVISION EXERCISE>Q 4
A man standing on the deck of a ship which is 10 m above the sea level, observes the angle of elevation of the top of the cloud as 30° and angle of depression of its reflection in the sea was found to be 60°. Find the height of the cloud and also the distance of the cloud from the man.
MEDIUM
10th CBSE
IMPORTANT
New Mathematics for Class X>Chapter 9 - Heights & Distances>REVISION EXERCISE>Q 5

From the top of a lighthouse the angle of depression of a ship sailing towards it was found to be 30°. After 10 seconds the angle of depression changes to 60°. Assuming that the ship is sailing at uniform speed, find how much time it will take in seconds to reach the lighthouse.

MEDIUM
10th CBSE
IMPORTANT
New Mathematics for Class X>Chapter 9 - Heights & Distances>REVISION EXERCISE>Q 6
From a point on the ground the angle of elevation of the bottom and the top of a flagstaff situated on the top of a 120 m tall house, was found to be 30° and 45° respectively. The height of the flagstaff is k3-1 m. Find k.
EASY
10th CBSE
IMPORTANT
New Mathematics for Class X>Chapter 9 - Heights & Distances>REVISION EXERCISE>Q 7
A person standing on the bank of a river observes that the angle of elevation of the top of the tree standing on the opposite bank is 60°. When he moves 30 m away from the bank, he finds the angle of elevation to be 30°. Find the height of the tree and the width of the river.
 
MEDIUM
10th CBSE
IMPORTANT
New Mathematics for Class X>Chapter 9 - Heights & Distances>REVISION EXERCISE>Q 8
The angle of elevation of a cloud from a point 60 m above the lake is 30° and the angle of depression of its reflection in the lake is 60°. Find the height of the cloud above the lake in m.
MEDIUM
10th CBSE
IMPORTANT
New Mathematics for Class X>Chapter 9 - Heights & Distances>REVISION EXERCISE>Q 9
From a point on the ground, the angles of elevation of the bottom and top of a transmission tower fixed at the top of 20 m high building are 45° and 60° respectively. The height of the transmission tower is k3-1 m. Find k.