A-LevelPhysicsPhysical quantities and units9702/22 · May/June 2018 · Q14 Marks
Define force.
- (a)Define force.[1]
- (b)State the SI base units of force.[1]
- (c)The force F between two point charges is given by F= Q1Q2 4πεr2 where Q₁ and Q₂ are the charges, ris the distance between the charges, ε is a constant that depends on the medium between the charges. Use the above expression to determine the base units of ε.[2]
Mark scheme
Marking points from the official mark scheme (May/June 2018). The mark or mark type is shown in brackets.
- [B1] rate of change of momentum
- [A1] kgms-2
- [C1] units for Q: As and for r: m
- [A1] units for ε = (As × As)/(kgms⁻² × m²) (= A²kg⁻¹m³s⁴)
Write your answer and get it marked
On Oracle Prep you can write or photograph your own answer and have it marked by AI against this mark scheme, with feedback on what you missed.
Sign up free →