हिंदी

Write an expression for the work done when a force is acting on an object in the direction of its displacement. - Science

Advertisements
Advertisements

प्रश्न

Write an expression for the work done when a force is acting on an object in the direction of its displacement.

लघु उत्तरीय

उत्तर

When a force F displaces a body through a distance S in the direction of the applied force, then the work done W on the body is given by the expression:

Work done = Force × Displacement

W = F × s

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 11: Work and Energy - Intext Questions [पृष्ठ १४९]

APPEARS IN

एनसीईआरटी Science [English] Class 9
अध्याय 11 Work and Energy
Intext Questions | Q 2 | पृष्ठ १४९

वीडियो ट्यूटोरियलVIEW ALL [1]

संबंधित प्रश्न

Define 1 J of work.


Express joule in terms of erg.


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)


Explain degradation of energy by taking two examples of your daily life.


Define 1 joule of work.


What is the work done against gravity when a body is moved horizontally along a frictionless surface?


When is the work done by a force on a body : (a) positive, (b) negative, and (c) zero?


A girl is carrying a school bag of 3 kg mass on her back and moves 200 m on a levelled road. If the value of g be 10 m/s2, the work done by the girl against the gravitational force will be :


Why does a spanner have a long handle?


A boy of mass m climbs up a staircase of vertical height h.

  1. What is the work done by the boy against the force of gravity?
  2. What would have been the work done if he uses a lift in climbing the same vertical height?

The K.E. of a body is 5 J. What will be its K.E. when its speed is doubled?

What is the amount of energy spent in lifting 1 kg through 1 m? Take g = 10 ms-2.

What is the difference between K.E. and P.E.?

Define the unit 'watt'. How is it related to horse power?

If an electric bulb of 100 watt is lighted for 2 hours, how much electric energy would be consumed?


Define the term work. Name the CGS and SI unit of work.


In the following case write yes, if the work is being done and no if no work is being done.

A boy climbing up a staircase.


Calculate the work done when:
A 5 kg weight is lifted 10 m vertically. (g = 9.8 m/s2)


A coolie is pushing a box weighing 1500 N up an inclined plane 7.5 m long on to a platform, 2.5 m above the ground.
(i) Calculate the mechanical advantage of the inclined plane. (ii) Calculate the effort applied by the coolie.
(iii) In actual practice, the coolie needs to apply more effort than what is calculated. Give one reason why you think the coolie needs to apply more effort.


Work done by this force at any instant is ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×