Question

sp8 physical science checkpoint2 2025 - 2026
a student sets up a circuit.
image of a circuit with a light bulb, wire, and battery
after 45 minutes, the light bulb starts becoming dimmer. after 60 minutes, the light bulb is no longer producing light. which statement provides the best conclusion?

• the battery lost a small amount of its mass
• all the electrons in the circuit were turned into light energy
• the light bulb destroyed all the available energy stored in the battery.
• all available energy stored in the battery was transformed into heat and light.

Explanation:

1. Option A is incorrect: The battery does not "lose mass" in a meaningful way for this circuit's energy depletion.
2. Option B is incorrect: Energy cannot be destroyed; it is transformed, not eliminated.
3. Option C is incorrect: Not all energy becomes light—some is always lost as heat in electrical circuits, which is why the bulb dims and fails as the battery's stored chemical energy is fully converted to these forms.
4. Option D is correct: The battery's stored chemical energy is converted into light (from the bulb) and thermal energy (heat, from resistance in the wire and bulb filament), following the law of conservation of energy.

Answer:

D. All available energy stored in the battery was transformed into heat and light.