中文（繁體）
中文（简体）
English
Displacement Method for Volume Paper 4: Error Clinic
Displacement Method for Volume Paper 4: Error Clinic
Ten real slips taken apart, from reading-as-volume to zero for a floating block.
Direct answers Answers and explanations for all ten questions
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: P5 Displacement Method for Volume |
| Level | P1 |
02 Questions (10 items)
- FoundationA cylinder starts at 100 mL and reads 150 mL after a stone is added. A student answers 150 cm cubed. What is correct?
- FoundationThe level goes from 75 mL to 115 mL and a student answers 115 cm cubed. What is the correct volume?
- FoundationA rectangular base is 20 cm by 5 cm and the water rises 3 cm. A student uses the perimeter 50 cm times 3 and answers 150 cm cubed. What is correct?
- IntermediateA student writes that 1 L is 100 cm cubed, so 3 L is 300 cm cubed. What is the correct answer?
- IntermediateFour identical beads raise the level from 40 mL to 100 mL and a student answers 60 cm cubed each. What is correct?
- IntermediateA container full to the brim holds 1 500 mL and 180 mL overflows when a stone is added. A student answers 1 500 cm cubed. What is correct?
- ChallengeA tank of base area 60 cm squared shows a rise of 2.5 cm and a student answers 60 cm cubed. What is the correct volume?
- ChallengeA wooden block floats and the level hardly moves, so a student answers that its volume is zero. What is wrong?
- ChallengeThe depth rises from 5 cm to 6.2 cm in a tank of base area 200 cm squared. A student multiplies 6.2 by 200 and answers 1 240 cm cubed. What is correct?
- Error redoTwo objects of 90 cm cubed each are put into water and a student counts only one and answers 90 cm cubed. How much water do both displace?
03 Answers and one-line notes
| # | Answer | One-line note |
|---|---|---|
| 1 | 50 cm cubed. The 150 is the final reading, so the original 100 mL must be subtracted. | Error: taking the reading as the volume. Fix: subtract the starting amount. |
| 2 | 40 cm cubed, using the rise of 40 rather than the final reading. | Error: the subtraction was skipped. Fix: always write final minus starting reading. |
| 3 | 300 cm cubed, since the base area is 100 cm squared and 100 times 3 gives the volume. | Error: the perimeter was used as an area. Fix: multiply only length by width. |
| 4 | 3000 cm cubed, because 1 L is 1 000 cm cubed and 3 times 1 000 is the answer. | Error: the litre conversion lost a zero. Fix: 1 L is 1 000 cm cubed. |
| 5 | 15 cm cubed, because the four share 60 mL and 60 divided by 4 gives one bead. | Error: the division by the number of pieces was missed. |
| 6 | 180 cm cubed. The overflow is the volume of the stone; the capacity of the container is irrelevant. | Error: the capacity was taken as the volume. Fix: read only the overflow. |
| 7 | 150.0 cm cubed, from 60 times 2.5. | Error: the rise was not multiplied in. Fix: base area times rise. |
| 8 | The block only floats, so it is not fully submerged and displaces less than its own volume. Press it under with a needle or tie on a weight, then measure the rise. | Error: assuming no rise means no volume. Fix: make the floating body sink fully. |
| 9 | 240.00000000000003 cm cubed. The rise is 1.2 cm, and 1 240 would be the water plus the object. | Error: the depth was used instead of the rise. Fix: subtract the original depth. |
| 10 | 180 cm cubed, from 90 times 2. | Error: the second object was left out. Fix: add each piece or multiply by the count. |
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.
Name the faulty step, give the correct method, then check with the readings.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.