The angle of elevation of a tower from a distance 50 m from its foot is 30°. The height of the tower is 

The shadow of the tower becomes 60 meters longer when the altitude of the sun changes from 45 ° to 30 °. Then the height of the tower is 

The shadow of a tower standing on a level plane is found to be 30 metre longer when the Sun's altitude changes from 60 ° to 45 °. The height of the tower is 

An Aeroplan is flying horizontally at a height of 1.8 km above the ground. The angle of elevation of plane from point X is 60° and after 20 seconds, its angle of elevation from X becomes 30°, If point X is on ground, then what is the speed (in km / hr.) of Aeroplan? 

A person from the top of a hill observes a vehicle moving towards him at a uniform speed. It takes 10 minutes for the angle of depression to change from 45 ° to 60 °. After this the time required by the vehicle to reach the bottom of the hill is 

From a tower 125 metres high the angle of depression of two objects, which are horizontal line through the base of the tower are 45° and 30° and they are on the same side of the tower. The distance (in metres) between the objects is

A ladder is placed along a wall such that its upper end is touching the top of the wall. The foot of the ladder is 10 ft away from the wall and the ladder is making an angle of 60 ° with the ground. When a man starts climbing on it, it slips and now ladder makes an angle of 30° with ground. How much did the ladder slip? 

The angle of elevation of ladder leaning against a house is 60° and the foot of the ladder is 6.5 meters from the house. The length of the ladder is