Foundation November 2023 Paper 3 Q14
14
(a) Show that the formula \(v = u + at\) can be rearranged to \(a = \dfrac{v - u}{t}\). [1]
(b) Use the formula \(a = \dfrac{v - u}{t}\) to find the acceleration, \(a\) m/s\(^2\), when a particle takes 4 seconds to increase from an initial velocity of 3 m/s to a final velocity of 9 m/s. [2]
| Answer | Marks | Part marks and guidance | |
|---|---|---|---|
| \(v - u = at\) seen as single statement | 1 | Accept e.g. \(-v + u = -at\) but not e.g. \(\dfrac{v - u}{t} = at \div t\) | |
| Answer | Marks | Part marks and guidance | |
|---|---|---|---|
| 1.5 oe | 2 | M1 for correct substitution \(\dfrac{9 - 3}{4}\) oe | e.g. \(1\frac{1}{2}\) or \(\frac{6}{4}\) or \(\frac{3}{2}\) For M1 accept a two-step evaluation with an arithmetic slip eg \(9 - 3 = 5\) followed by \(5 \div 4\) Do not accept \(\dfrac{3 - 9}{4}\) for M1 |