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सी.आई.एस.सी.ई.आईसीएसई ICSE Class 8

Write the expression for work done by a force. - Physics

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प्रश्न

Write the expression for work done by a force.

संक्षेप में उत्तर

उत्तर

Work done by applying force F is the product of the force applied on the body and distance moved by the body in the direction of force, work done = Force x distance moved in the direction of the force.
W = F × d

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अध्याय 4: Energy - Short/Long Answer questions [पृष्ठ ७७]

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सेलिना Concise Physics [English] Class 8 ICSE
अध्याय 4 Energy
Short/Long Answer questions | Q 7 | पृष्ठ ७७

संबंधित प्रश्न

Power spent by a body depends on the time for which it does work.


When does a force perform work?


A man lifts a mass of 20 kg to a height of 2.5 m. Assuming that the force of gravity on 1 kg mass is 10 N, find the work done by the man.


When is work said to be done by a force?


How much work is done when a body of mass m is raised to a height h above the ground?


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?


How many watts equal one horse power?


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What is the work done on a body by the gravitational force towards the centre of the path acting when it moves along a circular path?

How many joules are there in 1 mega joule?


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Give an example 
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(i) How much force would be needed to lift a drum into the truck directly/without using the plank? (Take g = 10 m/s2)

(ii) How much energy would be required in lifting the drum into the truck without the plank?

(iii) If the force needed to push the drum up the plank is 300 N, why is this less than the answer to part (i)?

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Mention whether work is done or not in the following activity.

S. No Activity Work done or not done
1. Pushing the door  
2. Holding a doll  
3. Sitting in a bus  
4. Pushing a wall  
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