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Work, Energy, and PowerClass 11thPhysics NCERT Exemplar Solutions Class 11th Chapter Sixphysics ncert solutions class 11thPhysics

A body of mass 0.5 kg travels in a straight line with velocity v = ax3/2 where a = 5 m-1/2s-1 . The work done by the net force during its displacement from x = 0 to x = 2 m is

(a) 1.5 J

(b) 50 J

(c) 10 J

(d) 100 J

3 Views|Posted 8 months ago
Asked by Shiksha User
1 Answer
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8 months ago

This is a multiple choice answer as classified in NCERT Exemplar

(b) v=ax3/2

m=0.5kg, a= 5m/s2

a= dv/dt= vdv/dt= ax3/2d/dx (ax3/2)

= ax3/2a * 3 2 * x1/2= 3/2a2x2

Force = ma= m 3 2 a2x2

Work done = ∫ 0 2 f d x = ∫ 0 3 3 2 m a 2 x 2 dx

= 3 2 ma2 (x3/3)02

= 1 2 m a 2 * 8 = 1 2 * ( 0.5 ) * 25 * 8 =50J

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Physics NCERT Exemplar Solutions Class 11th Chapter Six 2025

Physics NCERT Exemplar Solutions Class 11th Chapter Six 2025

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