DP Physics (last assessment 2024)
Question 18M.3.SL.TZ1.b
| Date | May 2018 | Marks available | [Maximum mark: 3] | Reference code | 18M.3.SL.TZ1.b |
| Level | SL | Paper | 3 | Time zone | TZ1 |
| Command term | Explain | Question number | b | Adapted from | N/A |
b.
[Maximum mark: 3]
18M.3.SL.TZ1.b
An experiment to find the internal resistance of a cell of known emf is to be set. The following equipment is available:
It is noticed that the resistor gets warmer. Explain how this would affect the calculated value of the internal resistance.
[3]
Markscheme
resistance of resistor would increase / be greater than 10 Ω
R + r «from ε = I(R + r)» would be overestimated / lower current
therefore calculated r would be larger than real
Award MP3 only if at least one previous mark has been awarded.
[3 marks]
