The Center of Mass of a System of Particles Remains

question 49

Multiple Choice

The center of mass of a system of particles remains at the same place if:

• A)it is initially at rest and the external forces sum to zero
• B)it is initially at rest and the internal forces sum to zero
• C)the sum of the external forces is less than the maximum force of static friction
• D)no friction acts internally
• E)none of the above

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