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Primary General Studies: Hong Kong Weather Warnings and Natural Hazards (Paper 3 (challenge))
Primary General Studies: Hong Kong Weather Warnings and Natural Hazards (Paper 3 (challenge))
Paper three asks for judgement and combination: deducing the warning level from rainfall, arrival time over a longer distance, metres per second, large-area water collection, average speed, percentage wind increase and duration.
Direct answers Find the threshold in judgement questions and the formula in calculation questions; handling the two types separately keeps your pace steady.
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: Hong Kong Weather Warnings and Natural Hazards |
| Level | parts of a closed circuit, conductors against insulators, series against parallel, adding up battery voltage, and electrical safety |
02 Questions (10 items)
- FoundationRainfall of forty-five millimetres in an hour belongs to which warning?
- FoundationA typhoon is eight hundred kilometres away and moves at twenty-five kilometres per hour. How long until closest approach?
- FoundationOne hundred and eighteen kilometres per hour is how many metres per second?
- IntermediateA roof of eighty square metres receives one hundred and twenty millimetres of rain. How many litres is collected?
- IntermediateA tropical cyclone covers nine hundred kilometres in thirty-six hours. What is its average speed?
- IntermediateNinety millimetres of rain falls in three hours. What is the hourly average?
- ChallengeWind speed rises from sixty-three to one hundred and eighteen kilometres per hour. What is the percentage increase?
- ChallengeA warning starts at 9:15 am and is cancelled at 6:45 pm. How long did it last?
- ChallengeThere are thirty rainstorm warnings in a year and black is one tenth of them. How many black warnings?
- Error redoA classmate says every tropical cyclone brings signal 8 to Hong Kong. What is wrong?
03 Answers and one-line notes
| # | Answer | One-line note |
|---|---|---|
| 1 | The amber rainstorm warning. | Forty-five is above thirty but below fifty, so it is amber. |
| 2 | Thirty-two hours. | Eight hundred divided by twenty-five is thirty-two. |
| 3 | About thirty-two point eight metres per second. | Divide by three point six: one hundred and eighteen gives about thirty-two point eight. |
| 4 | Nine thousand six hundred litres. | One square metre with one millimetre of rain gives one litre, so eighty times one hundred and twenty is nine thousand six hundred. |
| 5 | Twenty-five kilometres per hour. | Nine hundred divided by thirty-six is twenty-five. |
| 6 | Thirty millimetres per hour. | Ninety divided by three is thirty, exactly the amber threshold. |
| 7 | About eighty-seven point three per cent. | Take the gap of fifty-five, divide by sixty-three and multiply by one hundred. |
| 8 | Nine and a half hours. | Eighteen forty-five minus nine fifteen is nine hours thirty minutes. |
| 9 | Three. | Thirty times zero point one is three. |
| 10 | It overgeneralises; signal 8 is hoisted only when the wind reaches the threshold. | Most cyclones are far away or loosely organised and only bring signal 1 or 3. |
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.
Paper four clears the conductor, insulator and battery direction misconceptions.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.