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Work, Energy And Power

Question
CBSEENPH11020530

Two particles of masses m1,m2 move with initial velocities u1 and u2. On collision, one of the particles gets excited to a higher level, after absorbing energy (E). If final velocities of particles be v1 and v2, then we must have

  • straight m subscript 1 superscript 2 straight u subscript 1 space plus straight m subscript 2 superscript 2 straight u subscript 2 space minus straight epsilon space equals space straight m subscript 1 superscript 2 space straight v subscript 1 space plus straight m subscript 2 superscript 2 straight v subscript 2
  • 1 half m subscript 1 u subscript 1 superscript 2 space plus 1 half m subscript 2 u subscript 2 superscript 2 space equals space 1 half m subscript 1 v subscript 1 superscript 2 space plus 1 half m subscript 2 v subscript 2 superscript 2 minus epsilon
  • 1 half m subscript 1 u subscript 1 superscript 2 space plus 1 half m subscript 2 u subscript 2 superscript 2 space minus straight epsilon space equals space 1 half m subscript 1 v subscript 1 superscript 2 space plus 1 half m subscript 2 v subscript 2 superscript 2
  • 1 half m subscript 1 u subscript 1 superscript 2 space plus 1 half m subscript 2 u subscript 2 superscript 2 italic space italic plus epsilon space equals space 1 half m subscript italic 1 superscript italic 2 v subscript 1 superscript 2 space plus 1 half m subscript italic 2 superscript italic 2 v subscript 2 superscript 2

Solution

C.

1 half m subscript 1 u subscript 1 superscript 2 space plus 1 half m subscript 2 u subscript 2 superscript 2 space minus straight epsilon space equals space 1 half m subscript 1 v subscript 1 superscript 2 space plus 1 half m subscript 2 v subscript 2 superscript 2 Total space initial space energy space equals space 1 half straight m subscript 1 straight v subscript 1 superscript 2 space plus 1 half straight m subscript 2 straight v subscript 2 superscript 2
since space after space collision space one space particle space absorb space energy space straight epsilon space
therefore space Total space final space energy space equals space 1 half m subscript 1 v subscript 1 superscript 2 space plus 1 half m subscript 2 v subscript 2 superscript 2 italic space italic plus epsilon
F r o m italic space c o n s e r v a t i o n italic space o f italic space e n e r g y italic comma
rightwards double arrow space 1 half m subscript 1 u subscript 1 superscript 2 space plus 1 half m subscript 2 u subscript 2 superscript 2 space minus straight epsilon space equals space 1 half m subscript 1 v subscript 1 superscript 2 space plus 1 half m subscript 2 v subscript 2 superscript 2