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 Class 10                                                                     Marks: 20

Physics Revision


ATTEMPT ALL QUESTIONS.

Define moment of force. Write relationship between the SI and CGS unit of moment of couple. 2

Find the mass of the scale in equilibrium .  


                                      


Draw diagrams and locate the centre of gravity  of hollow cone and triangular sheet. 2

 State the  type of work done by a coolie  when i)  he lifts a load up ii) when he moves on a horizontal platform carrying load on his head.     2

A force is applied on a body of mass 20kg movong with a velocity of 40 m/s. The body attains a velocity of 50 m/s in 2  s. Calculate the work done by the force. 2

Give one example of  each  i) when chemical energy is converted into electrical energy .

                                                  Ii when electrical energy changes into sound  energy.   2

A ball of mass  200g is thrown vertically upwards with initial velocity of 20 m/s. Calculate its maximum potential energy.       2

State law of conservation of energy and prove it for a feely falling body taking any two points in the fall. 3

Give two conditions for which a force does no work. 2


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