In Fig. 12.58, what are the angles of depression from the observing positions `O_1` and `O_2` of the object at `A` ? (FIGURE)

From a point on a bridge across a river the angles of depression of the banks on opposite side of the river are 30^o and 45^o respectively. If bridge is at the height of 30m from the banks, find the width of the river.

From a point on a bridge across a river, the angles of depression of the banks on opposite sides of the river are 30^o and 45^o , respectively. If the bridge is at a height of 3 m from the banks, find the width of the river.

The angle of elevation of a stationery cloud from a point 2500 m above a lake is 15o and the angle of depression of its reflection in the lake is 45o . What is the height of the cloud above the lake level? (Use tan15o=0. 268 )

A man on the deck of a ship is 10m above the water level. He observes that the angle of elevation of the top of a cliff is 45o and the angle of depression of the base is 30o . Calculate the distance of the cliff from the ship and the height of the cliff.

An aeroplane at an altitude of 1200 metres finds that two ships are sailing towards it in the same direction. The angles of depression of the ships as observed from the aeroplane are 60^o and 30^o respectively. Find the distance between the two ships.

From the top of a cliff 300 metres high, the top of a tower was observed at an angle of depression 30^@ and from the foot of the tower the top of the cliff was observed at an angle of elevation 45^@ , The height of the tower is

On the same side of a tower, two objects are located. When observed from the top of the tower, their angles of depression are 45o and 60o . If the height of the tower is 150m, find the distance between the objects.

From the top of a building 60m high the angles of depression of the top and the bottom of a tower are observed to be 30o and 60o . Find the height of the tower.

What inferences would you derive from the following observations? dipole moment of H_2 O is 1.85 D.

A man standing on the deck of a ship, which is 8m above water level. He observes the angle of elevation of the top of a hill as 60o and the angle of depression of the base of the hill as 30o . Calculate the distance of the hill from the ship and the height of the hill.