A particle of mass 10 kg is moving with velocity 10 (x)^1/2, here x is displacement. The work done by net force during the displacement of particle from x=4 to x=9
Correct answer: D. 2500J
- A. 1250J
- B. 1000J
- C. 1500J
- D. 2500J
Explanation
Given : m= 10 kg v= 10√x m/s and dv/dx = 5/√x Now we know the formula; w= ma w= m(dv/dt) = m(dv/dt)(dx/dx) w= mv (dv/dx) Now we will apply the method of function w= f(x2-x1) mvdv w= f(9-4) 10 x 10 √x( 5/ √x) dx = 500(9-4) w= 2500 J Mathematically the other options are incorrect.
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The work-energy theorem states that the net work done on an object equals its change in kinetic energy. Questions involve positive and negative work, variable forces and force-displacement graphs, acceleration or deceleration, and the difference between this theorem and conservation of mechanical energy, which also requires attention to potential energy and non-conservative work.
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