Deep Dive: The Law of Conservation of Energy
Part of Energy Stores & Systems — GCSE Physics
This deep dive covers Deep Dive: The Law of Conservation of Energy within Energy Stores & Systems for GCSE Physics. Revise Energy Stores & Systems in Energy for GCSE Physics with 14 exam-style questions and 30 flashcards. This is a high-frequency topic, so it is worth revising until the explanation feels precise and repeatable. It is section 2 of 20 in this topic. Use this deep dive to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 2 of 20
Practice
14 questions
Recall
30 flashcards
🔬 Deep Dive: The Law of Conservation of Energy
Energy works exactly like money in a closed economy. You can't print money from nothing, and you can't destroy it — you can only move it from one account to another. When you "spend" energy heating a room, that energy hasn't vanished — it's been transferred to the thermal store of the air, walls, furniture, and eventually leaks outside.
The total always stays the same! This is called the First Law of Thermodynamics, and NOTHING in the universe has ever been found to violate it.
Why this matters for exams: Examiners will ALWAYS expect you to account for ALL the energy. If 100J goes in, 100J must come out — even if some is "wasted" as heat.
⚠️ FORBIDDEN PHRASES — never write these:
- "Energy is used up" — NO! Energy is transferred, not consumed
- "Energy is lost" — NO! Say "transferred to thermal store of surroundings"
- "Energy is created" — NO! Energy already exists, it's just moved
- "Energy disappears" — NO! It's dissipated (spread out), not gone
✓ CORRECT phrases to use: "Energy is transferred from... to...", "Energy is dissipated to the surroundings", "Energy is stored in the..."