4MA0 Higher January 2016 Paper 4R Q16
16 \(Q\) is inversely proportional to \(t^2\)
\(Q = 320\) when \(t = 0.5\)
Find a formula for \(Q\) in terms of \(t\)
(3)
| Scheme | Marks |
|---|---|
| \(Q = \dfrac{\text{"}k\text{"}}{t^2}\) | M1 |
| \(320 = \dfrac{\text{"}k\text{"}}{0.5^2}\) or “\(k\)” = 80 | M1 |
| \(Q = \dfrac{80}{t^2}\) | A1 |
| (3) |
Notes
M1: \(k\) must be a letter not a number
M1: for substitution (implies first M1)
A1: Award 3 marks for \(Q = \dfrac{\text{"}k\text{"}}{t^2}\) and “\(k\)” = 80 stated anywhere