Assertion (A): A man standing on a completely frictionless surface can propel himself by whistling.
Reason (R): If no external force acts on a system, its momentum cannot change.
A. Both (A) and (R) are true and (R) is the correct explanation of (A)
B. Both (A) and (R) are true, but (R) is not the correct explanation of (A)
C. (A) is true, but (R) is false
D. (A) is false, but (R) is true
Answer: Option B
Related Questions on Work, Energy and Power
Which of the following can do more work?
A. A raised hammer
B. A bullet fired by the gun
C. A moving stone
D. A rotating wheel
A. Energy released by a moving object
B. Energy emitted during mechanical work
C. The sum of the kinetic energy and potential energy of an object
D. Equal to the rate of work done
A. Chemical energy
B. Potential energy
C. Kinetic energy
D. Heat energy

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