NEET UG PHYSICS MCQ: WORK-ENERGY-POWER

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A sphere of mass m is tied to end of a string of length

l

and rotated through the other end along a horizontal circular path with speed v. The work done in full horizontal circle is

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Correct option: A

Option A is correct because in uniform circular motion, the force (tension in the string) is always perpendicular to the displacement, so no work is done.

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ball is dropped on the ground from a height of

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2\mathrm{\;m}{\mathrm{s}^{ - 1}}

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is A force

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on the particle is A motor is used to deliver water at a certain rate from a given pipe. To obtain 3 times water from same pipe in same time, by what factor should power of the motor be increased. A body projected vertically from the earth reaches a height equal to earth’s radius before returning to the earth. The power exerted by the gravitational force is greatest The speed limit of a car over a roadways bridge in the form of a vertical arc is

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