A man of a cliff observes a boat at an angle of depression of `30^0` which is approaching the shore to the point immediately beneath the observer with a uniform speed. Six minutes later, the angle of depression of the boat is found to be `60^0dot` Find the time taken by the boat to reach the shore.

A straight highway leads to the foot of a tower. A man standing at the top of the tower observes a car at an angle of depression of 30^@ , which is approaching the foot of the tower with a uniform speed. Six seconds later, the angle of depression of the car is found to be 60^@ . Find the time taken by the car to reach the foot of the tower from this point.

A straight highway leads to the foot of a tower. A man standing at the top of the tower observes a car at an angle of depression of 30^@ , which is approaching the foot of the tower with a uniform speed. Six seconds later, the angle of depression of the car is found to be 60^@ . Find the time taken by the car to reach the foot of the tower from this point.

A straight highway leads to the foot of a tower. A man standing at the top of the tower observes a car at angle of depression of 30^@ , which is approaching to the foot of the tower with a uniform speed. Six seconds later, the angle of depression of the car is found to be 60^@ . Find the further time taken by the car to reach the foot of the tower.

A man on a cliff observes a boat, at an angle of depression 30^(@) , which is sailing towards the shore to the point immediately beneath him. Three minutes later, the angle of depression of the boat is found to be 60^(@) . Assuming that the boat sails at a uniform speed, determine. how much more time it will take to reach the shore ?

A man on a cliff observes a boat, at an angle of depression 30^(@) , which is sailing towards the shore to the point immediately beneath him. Three minutes later, the angle of depression of the boat is found to be 60^(@) . Assuming that the boat sails at a uniform speed, determine. the speed of the boat in metre per second if the height of the cliff is 500 m

A man observes a car from the top of a tower, which is moving towards the tower with a uniform speed. If the angle of depression of the car change from 30^(@)" and "45^(@) in 12 minutes, find the time taken by the car now toreach the tower.

Form the top of a light house 60 m high with its base at the sea-level the angle of depression of a boat is 15^(@) . Find the distance of the boat from the foot of light house.

A man observes that when he moves up a distance c metres on a slope, the angle of depression of a point on the horizontal plane from the base of the slope is 30^0, and when he moves up further a distance c metres, the angle of depression of that point is 45^0dot The angle of inclination of the slope with the horizontal is.

From the top of a hill, the angles of depression of two consecutive kilometre stones due east are found to be 30^0a n d45^0 . Find the height of the hill.

An aeroplane at an altitude of 200 metres observes the angles of depression of opposite points on the two banks of a river to be 45^0a n d60^0dot Find the width of the river.