AQA Paper 2 2020 June — Question 15 5 marks

Exam BoardAQA
ModulePaper 2 (Paper 2)
Year2020
SessionJune
Marks5
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicNumerical integration
TypeTrapezium rule applied to real-world data
DifficultyModerate -0.8 Part (a) is a straightforward application of the trapezium rule with clearly defined stripsβ€”a routine numerical methods question requiring only substitution into a formula. Part (b) asks for an explanation of method (integration of a quadratic) rather than execution, which is even more basic. Both parts are standard textbook exercises with no problem-solving or insight required, making this easier than average.
Spec1.09f Trapezium rule: numerical integration3.02c Interpret kinematic graphs: gradient and area

A particle is moving in a straight line with velocity \(v\text{ ms}^{-1}\) at time \(t\) seconds as shown by the graph below. \includegraphics{figure_15}
  1. Use the trapezium rule with four strips to estimate the distance travelled by the particle during the time period \(20 \leq t \leq 100\) [4 marks]
  2. Over the same time period, the curve can be very closely modelled by a particular quadratic. Explain how you could find an alternative estimate using this quadratic. [1 mark]

Question 15:

AnswerMarks
15(a)States strip width = 20
PI by correct y values and not
AnswerMarks Guidance
contradicted. β„Ž1.1b B1
, ,
𝑦𝑦0 = 131 𝑦𝑦1 = 140
𝑦𝑦2 = 120 𝑦𝑦3 = 80 𝑦𝑦4 = 0
β„Ž
π΄π΄π΄π΄π‘†π‘†π‘Žπ‘Ž = (𝑦𝑦0+2𝑦𝑦1+2𝑦𝑦2+2𝑦𝑦3
2
Distance+ =𝑦𝑦 8 4 1)10 m
States five values PI
, ,
𝑦𝑦 , ,
𝑦𝑦0 = 131 𝑦𝑦1 = 140
If the𝑦𝑦y 2 u=se1 2h0=25𝑦𝑦 3 co=nd8o0ne𝑦𝑦 4 = 0
y =6, y =135, y =134,
0 1 2
y =94, y =0
3 4
If they use five strips between
20<t<100 condone
y =131, y =140, y =132,
0 1 2
y =108, y =67,y =0
3 4 5
Β±2on
AnswerMarks Guidance
Accept all y values1.1a M1
Applies correct trapezium rule
formula to their values (this mark
could be achieved with B0M0 so
AnswerMarks Guidance
far)1.1a M1
Applies trapezium rule with four
strips and obtains correct value for
distance. (accept values between
AnswerMarks Guidance
7970m and less than 8250m)1.1a A1
Subtotal4

AnswerMarks
15(b)Explains means of gaining a more
accurate estimate
For example, β€œintegrate the
quadratic between 20 and 100”
Must include limits for integration.
Or
Use the quadratic to calculate y
values in the trapezium rule or
other appropriate numerical
AnswerMarks Guidance
method.2.4 E1
the limits 20 and 100.
AnswerMarks Guidance
Subtotal1
Question Total5
QMarking Instructions AO
Question 15:
--- 15(a) ---
15(a) | States strip width = 20
PI by correct y values and not
contradicted. β„Ž | 1.1b | B1 | β„Ž = , 20 ,
, ,
𝑦𝑦0 = 131 𝑦𝑦1 = 140
𝑦𝑦2 = 120 𝑦𝑦3 = 80 𝑦𝑦4 = 0
β„Ž
π΄π΄π΄π΄π‘†π‘†π‘Žπ‘Ž = (𝑦𝑦0+2𝑦𝑦1+2𝑦𝑦2+2𝑦𝑦3
2
Distance+ =𝑦𝑦 8 4 1)10 m
States five values PI
, ,
𝑦𝑦 , ,
𝑦𝑦0 = 131 𝑦𝑦1 = 140
If the𝑦𝑦y 2 u=se1 2h0=25𝑦𝑦 3 co=nd8o0ne𝑦𝑦 4 = 0
y =6, y =135, y =134,
0 1 2
y =94, y =0
3 4
If they use five strips between
20<t<100 condone
y =131, y =140, y =132,
0 1 2
y =108, y =67,y =0
3 4 5
Β±2on
Accept all y values | 1.1a | M1
Applies correct trapezium rule
formula to their values (this mark
could be achieved with B0M0 so
far) | 1.1a | M1
Applies trapezium rule with four
strips and obtains correct value for
distance. (accept values between
7970m and less than 8250m) | 1.1a | A1
Subtotal | 4
--- 15(b) ---
15(b) | Explains means of gaining a more
accurate estimate
For example, β€œintegrate the
quadratic between 20 and 100”
Must include limits for integration.
Or
Use the quadratic to calculate y
values in the trapezium rule or
other appropriate numerical
method. | 2.4 | E1 | Integrates the quadratic between
the limits 20 and 100.
Subtotal | 1
Question Total | 5
Q | Marking Instructions | AO | Marks | Typical Solution
A particle is moving in a straight line with velocity $v\text{ ms}^{-1}$ at time $t$ seconds as shown by the graph below.

\includegraphics{figure_15}

\begin{enumerate}[label=(\alph*)]
\item Use the trapezium rule with four strips to estimate the distance travelled by the particle during the time period $20 \leq t \leq 100$
[4 marks]

\item Over the same time period, the curve can be very closely modelled by a particular quadratic.

Explain how you could find an alternative estimate using this quadratic.
[1 mark]
\end{enumerate}

\hfill \mbox{\textit{AQA Paper 2 2020 Q15 [5]}}