DP Physics (first assessment 2025)
Question 19M.1B.SL.TZ1.1a.i
Date | May 2019 | Marks available | [Maximum mark: 3] | Reference code | 19M.1B.SL.TZ1.1a.i |
Level | SL | Paper | 1B | Time zone | TZ1 |
Command term | Calculate | Question number | a.i | Adapted from | N/A |
a.i.
[Maximum mark: 3]
19M.1B.SL.TZ1.1a.i
(a.i)
Calculate the percentage error in the measured value of g.
[3]
Markscheme
error in m1 + m2 is 1 % OR error in m1 − m2 is 40 % OR error in a is 1 % ✔
adds percentage errors ✔
so error in g is 42 % OR 40 % OR 41.8 % ✔
Allow answer 0.42 or 0.4 or 0.418.
Award [0] for comparing the average value with a known value, e.g. 9.81 m s-2.
Examiners report
Atwoods machine a) is a quite straightforward question that tests the ability to propagate uncertainties through calculations. Almost all candidates proved the ability to add percentages or relative calculations, however, many weaker candidates failed in the percentage uncertainty when subtracting the two masses.

