A bird is sitting on the top of a vertical pole 20 m high and its elevation fron a point O on the ground is `45^@`,It Files off horizontally straight away from the point O.After one second , the elevation of the bird fron O is reduced to `30^@` Then the speed (in m/s) of the bird is

A bird is sitting on the top of a vertical pole 20 m high and its elevation from a point O on the ground is 45o . It flies off horizontally straight away from the point O. After one second, the elevation of the bird from O is reduced to 30o . Then the speed (in m/s) of the bird is (1) 40(sqrt(2)-1) (2) 40(sqrt(3)-2) (3) 20""sqrt(2) (4) 20(sqrt(3)-1)

A snake observes an eagle perching on the top of a pole 20 m high. Its elevation from snake s eye is 45^@ before it hies off horizontally straight away from the snake and after one second the elevation of the eagle reduces to 30^@ .The speed of the eagle is

The angle of elevation of the top of a tower from a point on the ground is 60^(@) . which is 25 m away from the foot of the tower. Find the height of the tower

A bird is sitting on the top of an 80 m high tree. From a point on the ground, the angle of elevation of the bird is 45^(@) . The bird flies away horizontally in such a way that it remained at a constant height from the ground. After 2 seconds, the angle of elevation of the bird from the same point is 30^(@) . Find the speed of flying of the bird. (Take sqrt3=1.732 ).

The angle of elevation of the loop of a vertical tower standing on a horizontal plane is observed to be 45^(@) from a point A on the plane. Let B be the point 30m vertically above the point A . If the angle of elevation of the top of the tower from B be 30^(@) , then the distance (in m) of the foot of the lower from the point A is:

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 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 angle of elevation of an aeroplane from a point on the ground is 45^@ . After a flight of 15 seconds, the elevation changes to 30^@ . If the aeroplane is flying at a height of 3000 metres, find the speed of the aeroplane.

A tower stands vertically on the ground. From a point on the ground, which is 15 m away from the foot of the tower, the angle of elevation of the top of the tower is found to be 60^@ . Find the height of the tower.

A tower stands vertically on the ground. From a point on the ground, which is 15 m away from the foot of the tower, the angle of elevation of the top of the tower is found to be 60^@ . Find the height of the tower.