An electrician has to repair an electric fault on a pole of height 4 m. He needs to reach a point 1.3 m below the top of the pole to un dertake the repair work the length of ladder that he should use, which when inclined at an angle of 60° to the horizontal would enable him to reach the required positions is :

The angle of elevation of sun changes form 30°to 45°, the length of the shadow of a pole decreases by 4 meters, the height of the pole is (Assume √3 = 1.732) 

Two poles of equal height are standing opposite to each other on either side of a road, which is 28 metre wide. From a point between them on the road, the angle of elevation  of the top are 30° and 60°. The height of each pole is:-

The distance between two pillars is 120 meters. The height of one pillar is thrice of the other pillar. The angles of elevation of their tops from the midpoint of the line connecting their feet are complementary to each other. The height (in metres) of the pillar is (use : √3 = 1.732 )

The shadow of a tower, when the angle of elevation of the sun is 60° is found to be 15 m shorter than when it is 45°. Then height of the tower is 

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 

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? 

A helicopter, at an altitude of 1500 metre, finds that two ships are sailing towards it, in the same direction. The angles of depression of the ships as observed from the helicopter are 60° and 30° respectively. Distance between the two ships, in metre is