Negative Work Can Be Done

question 66

Multiple Choice

Negative work can be done

• A) by friction on the tires while a car is accelerating without skidding.
• B) by a spring at the bottom of an elevator shaft when it stops a falling elevator.
• C) by a hand catching a ball.
• D) by all of the above.
• E) only by (b) and (c) above.

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Definitions:

Non-REM Sleep

A stage of sleep characterized by slower brain waves, reduced body movement, and absence of dreams, consisting of stages 1, 2, and deep stages 3 and 4.

Nightmares

Disturbing dreams that cause the dreamer to wake up feeling anxious and frightened.

REM Sleep

A stage of sleep characterized by rapid eye movements and is closely associated with vivid dreaming.

Postural Muscles

Muscles that are primarily responsible for maintaining posture and balance, enabling the body to stand upright and perform movements efficiently.