MCQ
When a body moves with some friction on a surface
  • A
    It loses kinetic energy but momentum is constant
  • B
    It loses kinetic energy but gains potential energy
  • Kinetic energy and momentum both decrease
  • D
    Mechanical energy is conserved

Answer

Correct option: C.
Kinetic energy and momentum both decrease
c
(c) Friction is a non-conservative external force to the system, it decreases momentum and kinetic energy both.

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