The angle of elevation of an aeroplane from a point A on the ground is `60^@`. After a flight' of 30 seconds, the angle of elevation changes to `30^@` . If the plane is flying at a constant height of `3600sqrt3 m`, find the speed of the plane in km/hour.

The angle of elevation of a jet plane from a point P on the ground is 60°.After a flight of 15 second the angle of elevation changes to 30°. If the jet plane is flying at a constant height of 1500sqrt3 ,find the speed of the jet plane in km/ hr.

The angle of elevation of the top of a tower from a point on the ground,which is 30m away from the foot of the tower,is 30^@ .Find the height of the tower.

The length of shadow of a tower on the plane ground is sqrt3 times the height of the tower.The angle of elevation of sun is

The angle of elevation of the top of a building from the foot of the tower is 30^@ and the angle of elevation of the top of the tower from the foot of the building is 60^@ .If the tower is 50 m high,find the height of the building

The angle of elevation of the top of a hill at the foot of the tower is 60° and the angle of elevation of the top of a tower from the foot of the hill is 30°.If the tower is 50m high, find the height of the hill.

The angle of elevation of the top of a tower at a point on a level ground is 30°.After walking a distance of 100mtowards the foot of the tower along the horizontal line through the foot of the tower on the same level ground, the angle of elevation of the top of the tower is 60°.Find the height of the tower.

The angle of elevation of the top of a tower as observed from a point on the ground is alpha and on moving 'a' metres towards the tower the angle of elevation is beta .Prove that the height of the tower is (atanalphatanbeta) / (tanbeta-tanalpha)

A man standing on a bank of a river found that the angles of elevation of a tree on the other bank of the river is 60^@ .By retiring 40m back,he found the angle of elevation to be 30^@ .Find the height of the tree and the breadth of the river.

A man in a boat moving away from a light house 100m high takes 2 minutes to change the angle of elevation of the top of light house from 60° to 30°,find the speed of the boat.

The angle of elevation of a temple is found to be 30^@ as seen from a place.By advancing 50m towards the temple the angle of its elevation is observed to be 45^@ .Find the height of the temple.