Question

which of the following best describes energy flow on earth? (1 point) \bigcirc earth is a closed system; only energy is exchanged with the surroundings. \bigcirc earth is an open system; only energy is exchanged with the surroundings. \bigcirc earth is a closed system; no matter or energy is exchanged with the surroundings. \bigcirc earth is an open system; no matter or energy is exchanged with the surroundings.

Explanation:

To determine the best description of energy flow on Earth, we analyze the concepts of open and closed systems:

• A closed system exchanges energy but not matter with its surroundings. Earth receives energy from the Sun (solar radiation) and emits energy (e.g., infrared radiation), but the amount of matter entering or leaving Earth is negligible (except for minor cosmic dust, etc.).
• An open system exchanges both matter and energy. Since Earth does not exchange significant matter with space, it is not an open system in terms of matter exchange.
• The third option is incorrect because Earth does exchange energy.
• The fourth option is incorrect as it misdefines an open system (open systems exchange matter/energy, and Earth does exchange energy).

So the correct statement is that Earth is a closed system; only energy is exchanged with the surroundings.

Answer:

A. Earth is a closed system; only energy is exchanged with the surroundings.