OCR M2 2014 June — Question 1 4 marks

Exam BoardOCR
ModuleM2 (Mechanics 2)
Year2014
SessionJune
Marks4
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicProjectiles
TypeFinding angle given constraints
DifficultyModerate -0.3 This is a straightforward two-part projectiles question using standard formulae. Part (i) requires applying the maximum height formula (v²sin²θ = 2gh) to find θ, and part (ii) uses the range formula. Both are direct applications of memorized results with minimal problem-solving, making it slightly easier than average but not trivial due to the algebraic manipulation required.
Spec3.02d Constant acceleration: SUVAT formulae3.02i Projectile motion: constant acceleration model

1 A football is kicked from horizontal ground with speed \(20 \mathrm {~ms} ^ { - 1 }\) at an angle of \(\theta ^ { \circ }\) above the horizontal. The greatest height the football reaches above ground level is 2.44 m . By modelling the football as a particle and ignoring air resistance, find
  1. the value of \(\theta\),
  2. the range of the football.

Question 1:
Part (i)
AnswerMarks Guidance
AnswerMarks Guidance
\((20\sin\theta)^2 - 2g(2.44) = 0\)M1 Use \(v^2 = u^2 + 2as\) vertically with \(v = 0\)
\(\theta = 20.2\)A1 \(\theta = 20.22908\ldots\)
[2]
Part (ii)
AnswerMarks Guidance
AnswerMarks Guidance
\(20\sin cv(\theta)t - \frac{1}{2}gt^2 = 0\) AND range \(= 20\,cv(t)\cos cv(\theta)\)M1 Use \(s = ut + \frac{1}{2}at^2\) vertically with \(s=0\) OR use \(v = u + at\) and doubles \(t\) AND horizontally with time found from vertical. \((t = 1.4113\ldots\) s or \(1.4093\ldots\)s (from 20.2))
Range \(= 26.5\) mA1 Range \(= 26.48541\ldots\) m or \(26.45387\ldots\)m (from 20.2)
[2]
OR
AnswerMarks Guidance
AnswerMarks Guidance
\(\dfrac{20^2\sin(2\times cv(\theta))}{g}\)M1 Use of range formula
Range \(= 26.5\) mA1 Range \(= 26.48541\ldots\) m or \(26.45387\ldots\)m (from 20.2)
[2]
## Question 1:

### Part (i)
| Answer | Marks | Guidance |
|--------|-------|----------|
| $(20\sin\theta)^2 - 2g(2.44) = 0$ | M1 | Use $v^2 = u^2 + 2as$ vertically with $v = 0$ |
| $\theta = 20.2$ | A1 | $\theta = 20.22908\ldots$ |
| **[2]** | | |

### Part (ii)
| Answer | Marks | Guidance |
|--------|-------|----------|
| $20\sin cv(\theta)t - \frac{1}{2}gt^2 = 0$ AND range $= 20\,cv(t)\cos cv(\theta)$ | M1 | Use $s = ut + \frac{1}{2}at^2$ vertically with $s=0$ OR use $v = u + at$ and doubles $t$ AND horizontally with time found from vertical. $(t = 1.4113\ldots$ s or $1.4093\ldots$s (from 20.2)) |
| Range $= 26.5$ m | A1 | Range $= 26.48541\ldots$ m or $26.45387\ldots$m (from 20.2) |
| **[2]** | | |

**OR**

| Answer | Marks | Guidance |
|--------|-------|----------|
| $\dfrac{20^2\sin(2\times cv(\theta))}{g}$ | M1 | Use of range formula |
| Range $= 26.5$ m | A1 | Range $= 26.48541\ldots$ m or $26.45387\ldots$m (from 20.2) |
| **[2]** | | |

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1 A football is kicked from horizontal ground with speed $20 \mathrm {~ms} ^ { - 1 }$ at an angle of $\theta ^ { \circ }$ above the horizontal. The greatest height the football reaches above ground level is 2.44 m . By modelling the football as a particle and ignoring air resistance, find\\
(i) the value of $\theta$,\\
(ii) the range of the football.

\hfill \mbox{\textit{OCR M2 2014 Q1 [4]}}