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The kinetic energy of an object depends ...

The kinetic energy of an object depends on the frame of reference in which its motion is measured. Give an example to illustrate this point.

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As you ride an express subway train, a backpack at your feet has no kinetic energy as meausured by you since according to you, the backpack is not moving. In the frame of reference of someone on the side of the tracks as the train rolls by the backpack is moving and has mass, and thus has kinetic energy.
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The kinetic energy of any body depends on the frame of reference of the observer. The kinetic energy is given by 1//2 mv_("rel")^(2) . Similarly the displacement of the object from different frames of reference will be: different. But the forces acting on the body remain unchanged. So work done by the forces as seen from: different frames will be different. But work energy! theorem will still be hold in every inertial reference' frame. For example, if a block of mass 2kg is moving with, velocity of 1m//s towards east on a rough surface, its KE = (1)/(2) xx 2 xx 1^(2) = 1J If it comes to rest, its KE = 0 work done by friction = K_(f) - k_(i) = -1 J If we observe it form a frame 2 moving with 1m//s toward east, its initial velocity will appear to be 1 - 1 = 0 Initial KE = (1)/(2) xx 2 xx 0^(2) = 0 Final velocity = 0 -1 = -1 Final KE = (1)/(2) xx 2 xx (-1)^(2) = 1J rArr Work done by friction = 1 - 0 = 1J What should be the velocity of an observer so that he will report the work done by friction on the block to be 0:

The kinetic energy of any body depends on the frame of reference of the observer. The kinetic energy is given by 1//2 mv_("rel")^(2) . Similarly the displacement of the object from different frames of reference will be: different. But the forces acting on the body remain unchanged. So work done by the forces as seen from: different frames will be different. But work energy! theorem will still be hold in every inertial reference' frame. For example, if a block of mass 2kg is moving with, velocity of 1m//s towards east on a rough surface, its KE = (1)/(2) xx 2 xx 1^(2) = 1J If it comes to rest, its KE = 0 work done by friction = K_(f) - k_(i) = -1 J If we observe it form a frame 2 moving with 1m//s toward east, its initial velocity will appear to be 1 - 1 = 0 Initial KE = (1)/(2) xx 2 xx 0^(2) = 0 Final velocity = 0 -1 = -1 Final KE = (1)/(2) xx 2 xx (-1)^(2) = 1J rArr Work done by friction = 1 - 0 = 1J According to passage:

The kinetic energy of any body depends on the frame of reference of the observer. The kinetic energy is given by 1//2 mv_("rel")^(2) . Similarly the displacement of the object from different frames of reference will be: different. But the forces acting on the body remain unchanged. So work done by the forces as seen from: different frames will be different. But work energy! theorem will still be hold in every inertial reference' frame. For example, if a block of mass 2kg is moving with, velocity of 1m//s towards east on a rough surface, its KE = (1)/(2) xx 2 xx 1^(2) = 1J If it comes to rest, its KE = 0 work done by friction = K_(f) - k_(i) = -1 J If we observe it form a frame 2 moving with 1m//s toward east, its initial velocity will appear to be 1 - 1 = 0 Initial KE = (1)/(2) xx 2 xx 0^(2) = 0 Final velocity = 0 -1 = -1 Final KE = (1)/(2) xx 2 xx (-1)^(2) = 1J rArr Work done by friction = 1 - 0 = 1J Choose correct statement :

The translational kinetic energy of an ideal gas depends only its

The kinetic energy of a particle depends on the square of speed of the particle. If error in measurement of speed is 30%, the error in the measurement of kinetic energy will be

Which of the following will not depend on orientation of frame of reference ?

Consider the following two statements . A : Kinetic energy depends on frame of reference . B : Linear momentum does not depend on frame of reference .

CENGAGE PHYSICS-WORK, POWER & ENERGY-Exercise 8.2
  1. A particle of mass 0.5kg travels in a straight line with velocity v=ax...

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  2. Can kinetic energy be negative? Explain.

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  3. The kinetic energy of an object depends on the frame of reference in w...

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  4. You are reshelving books in a library. You lift a book from the floor ...

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  5. What is the reason that we burn out our body fat only when we walk bri...

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  6. Figure shows three paths connecting points a and b, A single force F d...

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  7. The potential energy of a conservative force field is given by U=ax^...

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  8. A particle moves in x-y plane in figure under the influence of a frict...

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  9. A single conservative force acting on a particle varies as vecF=(-Ax+B...

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  10. A potential energy function for a two-dimensional force is the form U=...

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  11. For the potential energy curve shown in figure. (a) Determine whethe...

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  12. Is it possible exert a force which does work on a body without changin...

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  13. The kinetic friction force acting on a sliding body moving in a straig...

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  14. A single conservative force acting on a particle varies as vecF=(-Ax+B...

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  15. A block of mass m is placed at the bottom of a massless smooth wedge w...

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  16. A particle is projected in gravity with a speed v0. Using W-E theorem,...

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  17. A block is released from rest from a height h=5m. After travelling thr...

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  18. A block of mass m is connected with a rigid wall by light spring of st...

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  19. Two blocks of masses m1 and m2 inter connected by a spring of stiffnes...

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  20. A ball of mass m is thrown in air with speed v(1) from a height h(1) a...

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