Question

question 20 of 25
what happens to mass and energy in a closed system?

a. neither energy nor mass can enter or exit a closed system.

b. only energy can enter or exit a closed system.

c. only mass can enter or exit a closed system.

d. both energy and mass can enter or exit a closed system.

Explanation:

To solve this, we recall the definition of a closed system in physics (a subfield of Natural Science). A closed system is defined as a system where matter (mass) cannot enter or leave, but energy can be transferred across the system boundary. So we analyze each option:

• Option A: Incorrect. Energy can enter/exit a closed system.
• Option B: Correct. By definition, in a closed system, only energy (in forms like heat, work) can enter or exit; mass cannot.
• Option C: Incorrect. Mass cannot enter/exit a closed system.
• Option D: Incorrect. Mass cannot enter/exit a closed system.

Answer:

B. Only energy can enter or exit a closed system.