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NEET UG PHYSICS MCQ: WORK-ENERGY-POWER

1 Easy

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Application +4 | -1

A train is moving with a uniform velocity of

\left( {2\hat i - \hat j + 4\hat k} \right)\,m{s^{ - 1}}

. If the force required to overcome friction is

\left( {\hat i - 3\hat j + 2\hat k} \right)N

, the power of the engine is [watts]

View answer and explanation

Correct option: C

13

The correct answer is C. Power is the dot product of force and velocity. P = F · v = (1)(2) + (-3)(-1) + (2)(4) = 2 + 3 + 8 = 13 W.

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