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Primary General Studies: Energy and Saving Power (Paper 2 (intermediate))
Primary General Studies: Energy and Saving Power (Paper 2 (intermediate))
Paper two moves into calculation and application: the definition of a unit, energy labels, shower versus bath, then bills, solar output, carbon emissions and yearly savings.
Direct answers For bills, convert everything to units before multiplying by the price; for emissions, first ask how much one unit emits.
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: Primary General Studies: Energy and Saving Power |
| Level | parts of a closed circuit, conductors against insulators, series against parallel, adding up battery voltage, and electrical safety |
02 Questions (10 items)
- FoundationWhat is one unit of electricity?
- FoundationWhich label should you check when buying an appliance?
- FoundationWhy does a shower usually save more energy than a bath?
- IntermediateA home uses 150 units in a month at $1.2 per unit. What is the bill?
- IntermediateUsing 3 units a day, how many units in 30 days, and what does it cost at $1.2 per unit?
- IntermediateA 300 watt solar panel gets 5 hours of useful sunlight a day. How many units does it generate daily?
- ChallengeHow many units does the panel generate in 30 days?
- ChallengeAt 0.7 kg of carbon dioxide per unit, how much does 90 units emit?
- ChallengeSaving 6.12 units a month, how many units are saved in 12 months?
- Error redoA classmate says an appliance uses no power once the button is off. Is that right?
03 Answers and one-line notes
| # | Answer | One-line note |
|---|---|---|
| 1 | One kilowatt hour, the energy a 1000 watt appliance uses in one hour. | With this standard, different appliances can be compared fairly. |
| 2 | The energy efficiency label, where grade one is the most efficient. | For the same function, the lower the grade number the less energy it uses. |
| 3 | A shower heats less water, so it needs less energy. | A bath uses a large volume of hot water, so heating it takes much more energy. |
| 4 | $180. | 150 × 1.2 = 180 dollars. |
| 5 | 90 units, costing $108. | 3 × 30 = 90, and 90 × 1.2 = 108. |
| 6 | 1.5 units. | 300 × 5 = 1500 watt hours, which is 1.5 units. |
| 7 | 45 units. | 1.5 × 30 = 45 units. |
| 8 | 63 kg. | 90 × 0.7 = 63 kg. |
| 9 | 73.44 units. | 6.12 × 12 = 73.44 units. |
| 10 | No. An appliance still plugged in may draw standby power, so switch off the supply or unplug it. | Standby power is small, but it adds up over a long time. |
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.
Then try paper three, using voltage and current to work out power and resistance.Tutor Registration →
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