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CBSE Class 9 Answered

What are the advantages and disadvantages of friction?
Asked by suvdol | 24 Aug, 2008, 07:31: PM
answered-by-expert Expert Answer

Advantages : It helps us to walk , various parts of the machine are able to rotate due  to the friction between the belt and the pulley , it would be impossible to climb, fix nail, to drive if there were no friction.

Disadvantages : Wear and tear of machinery is due to friction , efficiency of machines decreases due to friction.

Answered by | 25 Aug, 2008, 01:11: AM

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CBSE 9 - Physics
An object of mass 1kg is falling from the height h=10m.calculate a) the total energy of an object at h=10m b) potential energy of the object when it is at h=4m c) kinetic energy of the object when it is at h=4m d) what will be the speed of the object when it hits the ground
Asked by mailtoparvathyprajith | 08 Feb, 2024, 06:45: PM
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CBSE 9 - Physics
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CBSE 9 - Physics
Why do we feel light on our feet when standing in a swimming pool with water up to our armpits ?
Asked by mailtoparvathyprajith | 08 Feb, 2024, 12:13: PM
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CBSE 9 - Physics
The average speed of a moving body can never be zero but the average velocity of a moving body can be zero. Justify.
Asked by mailtoparvathyprajith | 06 Feb, 2024, 09:50: PM
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CBSE 9 - Physics
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Asked by mailtoparvathyprajith | 06 Feb, 2024, 09:10: PM
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CBSE 9 - Physics
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Asked by mailtoparvathyprajith | 06 Feb, 2024, 09:00: PM
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CBSE 9 - Physics
when an arrow is shot from its bow it has kinetic Energy. From where does it get the kinetic Energy
Asked by mailtoparvathyprajith | 06 Feb, 2024, 08:44: PM
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CBSE 9 - Physics
If person A reaches the 2nd floor Of a shopping mall by lift and Person B reaches the same floor by stairs and both their masses are same. Is work done by person B is greater than Person A  against gravitational force.Justify your answer
Asked by mailtoparvathyprajith | 06 Feb, 2024, 08:24: PM
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CBSE 9 - Physics
calculate the amount of work required to stop a car of 1000kg moving with speed of 72km/h
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CBSE 9 - Physics
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Asked by mailtoparvathyprajith | 31 Jan, 2024, 06:55: PM
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