Advertisements
Advertisements
प्रश्न
A man carrying a suitcase in his hand is walking horizontally. What is the work done against gravity?
Advertisements
उत्तर
The displacement of the man and suitcase is along the horizontal direction. Thus, the angle between the displacement and the force of gravity is 90°;
Thus, W = Fd cos 90° = 0
Hence, no work is done against gravity in this case.
APPEARS IN
संबंधित प्रश्न
Define work.
A force of 30 N acts on a body and moves it through a distance of 5 m in the direction of force. Calculate the work done by the force.
A box of weight 150 kgf has gravitational potential energy stored in it equal to 14700 J. Find the height of the box above the ground. (Take g = 9.8 N kg-1)
How much work is done when a force of 2 N moves a body through a distance of 10 cm in the direction of force?
Name five appliances or machines which use an electric motor.
Name the physical quantity whose MKS units are kgm2s-3.
An electric motor drives a machine which lifts a mass of 4 kg through a height of 10 m in 5 s at a constant speed. Assuming g = 10 ms-2, calculate
(i) the amount of work done, (ii) the power of the machine.
Define Translational motion.
A man climbs a slope and another walks same distance on level road. Which of the two expends more energy and why?
A body of mass 0.5 kg travels on straight line path with velocity v = (3x2 + 4) m/s. The net work done by the force during its displacement from x = 0 tox = 2 m is ______.
