MYP Physics · 15 · data analysis
Test an inverse-square electric field
Fields and gravity · Original GioPhysics question with a detailed, mark-by-mark answer guide.
- Demand
- discriminating
- Marks
- 7
- Topics
- 3
- Answer
- Complete
Electric field around the point charge
The plotted points reproduce the two columns of the question table, in the original units.
Vertical axis (y): Field magnitude / N C⁻¹
Horizontal axis (x): Distance from charge / m
Read the exact data as a table
| Distance from charge / m | Field magnitude / N C⁻¹ |
|---|---|
| 0.1 | 360 |
| 0.2 | 90 |
| 0.3 | 40 |
| 0.4 | 22.5 |
These are the supplied values, not a worked answer. No fitted trend is drawn.
A simulation reports the electric field magnitude at different distances from one isolated positive point charge.
| Distance from charge / m | Field magnitude / N C⁻¹ |
|---|---|
| 0.10 | 360 |
| 0.20 | 90 |
| 0.30 | 40 |
| 0.40 | 22.5 |
- a
Show Use two data pairs to show that the field follows an inverse-square pattern.
3 marks - b
Predict Predict the field magnitude at 0.50 m.
2 marks - c
Evaluate State two reasons why a classroom field-line diagram is not a literal picture of this field.
2 marks
Ready to self-mark?Reveal the detailed answer guide
a
Show Use two data pairs to show that the field follows an inverse-square pattern.
Read the data before explaining it. Quote the relevant values or trend, show the comparison or calculation, and then connect that numerical evidence to the physical conclusion—including uncertainty or anomalies when they matter.
- 1
Selects two suitable distances, such as 0.10 m and 0.20 m.
- 2
Shows that distance doubles while field falls from 360 to 90 N C⁻¹, a factor of four.
- 3
Connects a factor-four decrease to 1 ÷ 2², supporting E ∝ 1/r².
b
Predict Predict the field magnitude at 0.50 m.
Read the data before explaining it. Quote the relevant values or trend, show the comparison or calculation, and then connect that numerical evidence to the physical conclusion—including uncertainty or anomalies when they matter.
- 1
Uses the constant Er² = 360 × 0.10² = 3.6 N m² C⁻¹.
- 2
Calculates E = 3.6 ÷ 0.50² = 14.4 N C⁻¹.
c
Evaluate State two reasons why a classroom field-line diagram is not a literal picture of this field.
Read the data before explaining it. Quote the relevant values or trend, show the comparison or calculation, and then connect that numerical evidence to the physical conclusion—including uncertainty or anomalies when they matter.
- 1
States that the lines are a chosen representation and there are not physical threads in space.
- 2
States another limitation, such as line number or spacing being chosen, a flat drawing representing a three-dimensional field, or arrows showing test-charge direction rather than motion.
Private on this device