Height and Distance - Practice Questions & MCQ

 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 45⁰.  It flies off horizontally straight away from the point O.After one second, the elevation of the bird from O is reduced to 30⁰. Then the speed (in m/s) of the bird is :

The angle of elevation of the top of a vertical tower from a point A, due east of it is 45⁰.  The angle of elevation of the top of the same tower from a point B, due south of A is 30⁰.  If the distance between A and B is m , then the height of the tower (in metres), is :

 Two ships A and B are sailing straight away from a fixed point O along routes such that AOB is always 120⁰. At a certain instance, OA = 8 km, OB = 6 km and the ship A is sailing at the rate of 20 km/hr while the ship B sailing at the rate of 30 km/hr. Then the distance between A and B is changing at the rate (in km/hr) :

 If the angles of elevation of the top of a  tower from three collinear points A, B and C, on a line leading to the foot of the

tower, are 30⁰, 45⁰ and 60⁰ respectively,then the ratio, AB : BC, is :