Advertisements
Advertisements
प्रश्न
In which of the following cases, is work being done?
(i) A man pushing a wall.
(ii) a coolie standing with a load of 12 kgf on his head.
(iii) A boy climbing up a staircase.
Advertisements
उत्तर
Work is done only in case of a boy climbing up a stair case.
संबंधित प्रश्न
Work is said to be done by a forte only when ................
The energy of a body is its capacity to do .........
Find the kinetic energy of a body of mass 1 kg moving with a uniform velocity of 10 m s-1.
A max X goes to the top of a building by a vertical spiral staircase. Another man Y of the same mass goes to the top of the same building by a slanting ladder. Which of the two does more work against gravity and why?
A body of mass 60 kg has the momentum 3000 kgm/s-1. Calculate: the speed of the body.
What is the difference between renewable and non-renewable resources?
(i) A 200g ball is thrown vertically upward with an initial velocity of 30 ms-1. Draw a velocity-time graph for the motion of ball.
(ii) How long will the ball take to reach the highest point?
(iii) What will be the kinetic energy of ball, when it returns to the starting point, neglecting the air resistance?
(iv) What will be the potential energy of ball at highest point?
