A System Is Acted on by Its Surroundings in Such

question 21

Multiple Choice

A system is acted on by its surroundings in such a way that it receives 50 J of heat while simultaneously doing 70 J of work.What is its net change in internal energy?

• A) 70 J
• B) −20 J
• C) zero
• D) 20 J

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Definitions:

Posthypnotic Instructions

Suggestions given to a person during hypnosis that are intended to be acted upon after the person emerges from the hypnotic state.

Hypnosis

A trance-like state of heightened focus and concentration, often used for therapeutic purposes or suggestion.

Relaxation

A state of reduced tension and stress, characterized by a calm and peaceful mind and body.

Sleep Spindles

Brief bursts of brain activity detectable in EEG recordings during stage 2 of non-REM sleep, associated with learning, memory consolidation, and protection of sleep.