If the Total Momentum of a System Is Changing

question 31

Multiple Choice

If the total momentum of a system is changing:

• A)particles of the system must be exerting forces on each other
• B)the system must be under the influence of gravity
• C)the center of mass must have constant velocity
• D)a net external force must be acting on the system
• E)none of the above

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Definitions:

Myelination

The process of forming a myelin sheath around nerves to increase the speed at which impulses propagate.

Visual Information

Data or knowledge received and processed by the visual system, usually pertaining to the sense of sight and visual perception.

Preoperational Children

A stage in Jean Piaget's theory of cognitive development, usually from ages 2 to 7, where children are beginning to engage in symbolic play but are not yet capable of logical thought.

Theory of Mind

The ability to attribute mental states—beliefs, intents, desires, emotions—to oneself and others, and to understand that others have beliefs and perspectives different from one's own.