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S1 Science: Energy Forms and Conversion (Paper 1: basics)
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S1 Science: Energy Forms and Conversion (Paper 1: basics)
The first paper builds the base: sort out the forms of energy, recall conservation, and divide the useful output by the total input to get efficiency.
Direct answers Write down the input and the useful output before starting each sum and far fewer mistakes appear.
01 Paper details (check answers afterwards)
| Item | Detail |
|---|---|
| Questions | 10 |
| Suggested time | 20 |
| Difficulty mix | Foundation 3 · Intermediate 3 · Challenge 3 · Error redo 1 |
| Chapter | Chapter: S1 Science: Energy Forms and Conversion |
| Level | S1 Science |
02 Questions (10 items)
- FoundationWhich two forms of energy does a lamp mainly convert electrical energy into?
- FoundationWhat does the law of conservation of energy state?
- FoundationWhich form of energy does a stone gain when it is lifted higher?
- IntermediateA bulb takes in 100 J of electrical energy and gives 20 J of light. What is its efficiency?
- IntermediateA motor takes in 500 J and delivers 150 J of useful work. What is its efficiency?
- IntermediateA machine is 80 per cent efficient and takes in 250 J. How much useful output does it give?
- Challenge1 000 J of energy is converted in 10 seconds. What is the power?
- ChallengeA 60 W lamp is left on for 5 minutes. How much energy does it use?
- ChallengeA machine is 25 per cent efficient and takes in 2 000 J. How much energy is wasted?
- Error redoA student says a fan turns all its electrical energy into kinetic energy. What is wrong?
03 Answers and one-line notes
| # | Answer | One-line note |
|---|---|---|
| 1 | Light energy and heat energy | A lamp gives out light and heat at the same time, and the heat cannot be avoided. |
| 2 | Energy is never lost, it only changes from one form to another | The total amount stays the same and only the form changes, which is why no energy comes free. |
| 3 | Potential energy (gravitational potential energy) | Energy stored because of the higher position is potential energy, which turns into kinetic energy when released. |
| 4 | 20 per cent | 20 divided by 100 times one hundred per cent is 20 per cent, and the other 80 J becomes heat. |
| 5 | 30 per cent | 150 divided by 500 times one hundred per cent is 30 per cent. |
| 6 | 200 J | 80 per cent of 250 J is 200 J, and the other 50 J leaves as heat and sound. |
| 7 | 100 W | Power is energy divided by time, so 1 000 divided by 10 gives 100 W. |
| 8 | 18 000 J | Five minutes is 300 seconds, and 60 times 300 gives 18 000 J. |
| 9 | 1 500 J | The useful output is 500 J, so 2 000 minus 500 leaves 1 500 J lost as heat and sound. |
| 10 | Sound and heat are ignored, so kinetic energy is only part of the output | The blades vibrate to make sound and the bearings and coil warm up, so the efficiency must stay below 100 per cent. |
04 What to do after marking
- After marking, redo only the wrong items and write down which step went wrong (formula, unit, or misread number).
- Repeat the same item two days later; move to the next paper only when both attempts are correct.
- Parents only need the answer and note columns; there is no need to explain every item.
Three basics: energy takes many forms but the total is conserved, a raised stone stores potential energy while a moving body carries kinetic energy, and efficiency is the useful output over the total input times one hundred per cent.Tutor Registration →
Questions and answers are written originally by the TutorZone team and are not taken from any school, publisher or examination authority paper. Every value is checked by computer.