When the speed of a moving object is doubled, its:A. acceleration is d

1.	When the speed of a moving object is doubled, its:A. acceleration is doubled B. weight is doubled C. kinetic energy is doubled D. kinetic energy increases 4 times
Answer» Kinetic energy KE of a body of mass m moving with velocity or speed v is given by the formula: KE₁ = \(\frac{1}{2}\)mv₁² If the speed of particle is doubled then KE₂ = \(\frac{1}{2}\)mv₂² where, v₂ = 2v₁ Substituting the value of v₂ in the formula, KE₂ = \(\frac{1}{2}\)m(2v₁)² = \(\frac{1}{2}\) (4mv₁² ) KE₂ = 4 KE₁ So kinetic energy will become 4 times if the speed is doubled. On other hand, acceleration depends on final as well as initial velocity, and here acceleration will be same. Weight is independent of change in speed.

When the speed of a moving object is doubled, its:A. acceleration is doubled B. weight is doubled C. kinetic energy is doubled D. kinetic energy increases 4 times

Answer»

Kinetic energy KE of a body of mass m moving with velocity or speed v is given by the formula:

KE₁ = \(\frac{1}{2}\)mv₁²

If the speed of particle is doubled then

KE₂ = \(\frac{1}{2}\)mv₂² where, v₂ = 2v₁

Substituting the value of v₂ in the formula,

KE₂ = \(\frac{1}{2}\)m(2v₁)²

= \(\frac{1}{2}\) (4mv₁² )

KE₂ = 4 KE₁

So kinetic energy will become 4 times if the speed is doubled.

On other hand, acceleration depends on final as well as initial velocity, and here acceleration will be same.

Weight is independent of change in speed.

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