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Karnataka Board PUCPUC Science Class 11

A body is moving unidirectionally under the influence of a source of constant power supplying energy. Which of the diagrams shown in figure correctly shows the displacement-time curve for its motion?

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Question

A body is moving unidirectionally under the influence of a source of constant power supplying energy. Which of the diagrams shown in figure correctly shows the displacement-time curve for its motion?

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MCQ
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Solution


Explanation:

For constant power

Displacement ∝ t3/2

Because P = `(vecF * dvecs)/(dt) = vecF * vecv` = constant .....(∵ P = constant according to the problem)

Now, will by dimensional analysis

[F][v] = constant

⇒ [MLT–2][LT–1] = constant

⇒ L2T–3 = constant  .....(∵ mass is constant)

⇒ L ∝ T3/2 

⇒ Displacement (d) ∝ t3/2

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Chapter 6: Work, Energy and Power - Exercises [Page 41]

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NCERT Exemplar Physics Exemplar [English] Class 11
Chapter 6 Work, Energy and Power
Exercises | Q 6.11 | Page 41

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