| Exam Board | AQA |
|---|---|
| Module | Further Paper 3 Mechanics (Further Paper 3 Mechanics) |
| Year | 2024 |
| Session | June |
| Marks | 10 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Impulse and momentum (advanced) |
| Type | Collision with fixed wall |
| Difficulty | Standard +0.3 This is a standard oblique collision mechanics problem requiring resolution of velocities parallel and perpendicular to the wall, application of Newton's experimental law (e=0.7), and impulse calculation. While it involves multiple steps and careful component work, it follows a well-established procedure taught in Further Maths mechanics with no novel insight required. The final part tests conceptual understanding of friction effects. |
| Spec | 6.03i Coefficient of restitution: e6.03k Newton's experimental law: direct impact6.03l Newton's law: oblique impacts |
| Answer | Marks |
|---|---|
| 7(a)(i) | Forms two expressions for motion |
| Answer | Marks | Guidance |
|---|---|---|
| perpendicular to the wall. | 3.3 | M1 |
| Answer | Marks | Guidance |
|---|---|---|
| Obtains two correct expressions. | 1.1b | A1 |
| Eliminates θ to find a value for v | 1.1a | M1 |
| Obtains AWRT 3.9 | 1.1b | A1 |
| Subtotal | 4 | |
| Q | Marking Instructions | AO |
| Answer | Marks |
|---|---|
| 7(a)(ii) | Uses their value for v or eliminates |
| Answer | Marks | Guidance |
|---|---|---|
| sin θ or cos θ | 3.4 | M1 |
| Answer | Marks | Guidance |
|---|---|---|
| Obtains AWRT 50 | 1.1b | A1 |
| Subtotal | 2 | |
| Q | Marking Instructions | AO |
| Answer | Marks |
|---|---|
| 7(a)(iii) | Uses the impulse equation with |
| Answer | Marks | Guidance |
|---|---|---|
| opposite signs. | 3.4 | M1 |
| Answer | Marks | Guidance |
|---|---|---|
| Condone missing/incorrect units. | 1.1b | A1 |
| Subtotal | 2 | |
| Q | Marking Instructions | AO |
| Answer | Marks | Guidance |
|---|---|---|
| 7(b) | Explains what happens to one | |
| component of the impulse. | 2.4 | M1 |
| Answer | Marks | Guidance |
|---|---|---|
| increase. | 2.4 | R1 |
| Subtotal | 2 | |
| Question total | 10 | |
| Q | Marking Instructions | AO |
Question 7:
--- 7(a)(i) ---
7(a)(i) | Forms two expressions for motion
by resolving parallel and
perpendicular to the wall. | 3.3 | M1 | 5cos 60° = vcos θ
0.7 × 5sin 60° = vsin θ
v = ( 5 c o s 6 0 ) 2 + ( 3 . 5 s in 6 0 ) 2
= 3 . 9
Obtains two correct expressions. | 1.1b | A1
Eliminates θ to find a value for v | 1.1a | M1
Obtains AWRT 3.9 | 1.1b | A1
Subtotal | 4
Q | Marking Instructions | AO | Marks | Typical Solution
--- 7(a)(ii) ---
7(a)(ii) | Uses their value for v or eliminates
v to find an expression for tan θ,
sin θ or cos θ | 3.4 | M1 | 3.5sin 60
tan θ =
5cos60
θ =50
Obtains AWRT 50 | 1.1b | A1
Subtotal | 2
Q | Marking Instructions | AO | Marks | Typical Solution
--- 7(a)(iii) ---
7(a)(iii) | Uses the impulse equation with
components of velocities
perpendicular to the wall with
opposite signs. | 3.4 | M1 | I = 0.2 × 3.929sin 50.48°
– (–0.2 × 5sin 60°)
= 1.5 Ns
Obtains AWRT 1.5.
Must be positive.
Condone missing/incorrect units. | 1.1b | A1
Subtotal | 2
Q | Marking Instructions | AO | Marks | Typical Solution
--- 7(b) ---
7(b) | Explains what happens to one
component of the impulse. | 2.4 | M1 | Any friction would not cause a
change in the velocities
perpendicular to the wall and so
the magnitude of the component of
the impulse perpendicular to the
wall would be unchanged.
There will be a component of the
impulse parallel to the wall and so
the magnitude of the total impulse
would increase.
Explains what will happen to the
other component of the impulse
and that the magnitude will
increase. | 2.4 | R1
Subtotal | 2
Question total | 10
Q | Marking Instructions | AO | Marks | Typical Solution
A sphere, of mass 0.2 kg, moving on a smooth horizontal surface, collides with a fixed wall.
Before the collision the sphere moves with speed 5 m s$^{-1}$ at an angle of 60° to the wall.
After the collision the sphere moves with speed $v$ m s$^{-1}$ at an angle of $\theta$° to the wall.
The velocities are shown in the diagram below.
\includegraphics{figure_7}
The coefficient of restitution between the wall and the sphere is 0.7
\begin{enumerate}[label=(\alph*)]
\item Assume that the wall is smooth.
\begin{enumerate}[label=(\roman*)]
\item Find the value of $v$
Give your answer to two significant figures.
[4 marks]
\item Find the value of $\theta$
Give your answer to the nearest whole number.
[2 marks]
\item Find the magnitude of the impulse exerted on the sphere by the wall.
Give your answer to two significant figures.
[2 marks]
\end{enumerate}
\item In reality the wall is not smooth.
Explain how this would cause a change in the magnitude of the impulse calculated in part (a)(iii).
[2 marks]
\end{enumerate}
\hfill \mbox{\textit{AQA Further Paper 3 Mechanics 2024 Q7 [10]}}