NEET-XII-Physics

23: Heat and Temperature

with Solutions - page 3
Qstn# iii-3 Prvs-QstnNext-Qstn
  • #3
    A body A is placed on a railway platform and an identical body B in a moving train. Which of the following energies of B are greater than those of A, as seen from the ground?
    (a) Kinetic
    (b) Total
    (c) Mechanical
    (d) Internal
    digAnsr:   a,b,c
    Ans : (a) Kinetic
    (b) Total
    (c) Mechanical
    As body A is at rest on the ground, it possesses only potential energy, whereas body B, being placed inside a moving train, possesses kinetic energy due to its motion along with the train. Therefore, body B will have greater kinetic, mechanical (energy possessed by the body by virtue of its position and motion = kinetic energy+potential energy) energy and, hence, total (sum of all the energies) energy. No information is given about the temperature of the body so we can not say wheather body B' s internal energy will be or will not be greater than that of body A.
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