A labourer standing near the top of an old wooden step ladder feels unstable. Why ?

A person standing on the top of a building of height 60sqrt(3) feel observed the top of a tower to lie at an elevation of 45^(@) . That person descended to the bottom of the building and found that the top of the same tower is now at an angle of elevation of 60^(@) . The height of the tower (in feet) is

A person standing near the edge of the top of a building throws two balls A and B. The ball A is thrown vertically upward and B is thrown vertically downward with the same speed. The ball A hits the ground with speed v_A and the ball B hits the ground wiht a speed v_B . We have

A boy climbed an old step ladder (which has a tendency to slip) and observed that he feels more unstable when standing at the top of the ladder than at the bottom most step. Explain the observation with reasoning

You feel hot while standing in sunlight, but cool in the shade of a building. Why?

There was some construction work going on in the neighbourhood of Amar Singh. One day when Amar Singh came back form his office, he saw his ten year old son standing near the welder and looking at the electric welding being done with great curiosity. Amar Singh grabbed his son by the arm and brought him inside the house quickly. He firmly told his son not to look at electric welding being done again because it is extremely harmful. Amar Singh then went out and scolded the welder for allowing a child to stand near him and watch the electric welding being done. The welder said 'sorry' to Amar Singh for the lapse on his part. (a) Why did Amar sing bring his son inside the house quickly ? (b) What harm could have been done to the child by staring at the electric welding and Why ? (c) Name a natural luminous object which can do the same damage when looked at straight with naked eye for a considerable time. (d) What other harm could have been done to the child by standing near the welder when electric welding was being done ? (e) What value are exhibited by Amar Singh in this episode ?

A weightless ladder 6m long rests against a frictionless wall at an angle of 60^(@) from the horizontal. A 60kg man standing on it is 2m from the top of the ladder. A horizontal force is applied at the lower end to keep it from slipping. The magnitude of the force is

A ladders is more likely to slip when a person is near the top than when he is near the bottom. The friction between the ladder and floor decreases as he climbs up.

A fire engine, standing near a building, extends its ladder to a length of 10 metres to reach a certain window in the building. What is the height of the window from the ground?