DP Physics (last assessment 2024)
Question 22N.2.SL.TZ0.b.i
| Date | November 2022 | Marks available | [Maximum mark: 2] | Reference code | 22N.2.SL.TZ0.b.i |
| Level | SL | Paper | 2 | Time zone | TZ0 |
| Command term | Show that | Question number | b.i | Adapted from | N/A |
b.i.
[Maximum mark: 2]
22N.2.SL.TZ0.b.i
Resistor R is connected in a circuit with a cell that has internal resistance.
The ammeter and the voltmeter are ideal.
The cell has an emf of 1.49 V. The resistance of R is 50.0 Ω. The voltmeter reads 1.47 V.
Show that the internal resistance of the cell is about 0.7 Ω.
[2]
Markscheme
current «A» ✓
r OR «Ω» ✓
For MP2, allow any other correctly substituted expression for r.
Examiners report
Many answers here produced a number that did not round to 0.7 but students claimed it did. The simultaneous equation approach was seen in the best candidates, getting the right answer. It is worthy of reminding about the need of showing one more decimal place when calculating a show that value type of question.
