CAIE M2 2018 June — Question 1 6 marks

Exam BoardCAIE
ModuleM2 (Mechanics 2)
Year2018
SessionJune
Marks6
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicProjectiles
TypeProjectile passing through given point
DifficultyStandard +0.3 This is a straightforward projectiles question requiring standard SUVAT equations in two dimensions. Students must resolve motion horizontally (constant velocity) and vertically (constant acceleration), then use simultaneous equations to find angle and speed. The calculations are routine with no conceptual surprises, making it slightly easier than average for A-level mechanics.
Spec3.02d Constant acceleration: SUVAT formulae3.02i Projectile motion: constant acceleration model

\includegraphics{figure_1} A small ball \(B\) is projected from a point \(O\) on horizontal ground towards a point \(A\) 12 m above the ground. 0.9 s after projection \(B\) has travelled a horizontal distance of 20 m and is vertically below \(A\) (see diagram).
  1. Find the angle and the speed of projection of \(B\). [4]
  2. Calculate the distance \(AB\) when \(B\) is vertically below \(A\). [2]

Question 1:

AnswerMarks Guidance
1(i)tanθ = 12/20 M1
θ ( = 30.96) = 31(.0)°A1
20
Vcos30.96 =
AnswerMarks Guidance
0.9M1 Use horizontal motion. Allow their θ for the M mark.
V = 25.9 ms−1A1
Total:4

AnswerMarks
1(ii)0.92
H = 25.9sin31 × 0.9 – g × ( = 7.948)
AnswerMarks Guidance
2M1 1
Use s = ut + at2 vertically. H is the height above the ground.
2
Allow their V and θ for the M mark.
AnswerMarks Guidance
AB ( = 12 – 7.95) = 4.05 mA1 Allow AB = 4.06
Total:2
Question 1:
--- 1(i) ---
1(i) | tanθ = 12/20 | M1 | θ is the angle of projection
θ ( = 30.96) = 31(.0)° | A1
20
Vcos30.96 =
0.9 | M1 | Use horizontal motion. Allow their θ for the M mark.
V = 25.9 ms−1 | A1
Total: | 4
--- 1(ii) ---
1(ii) | 0.92
H = 25.9sin31 × 0.9 – g × ( = 7.948)
2 | M1 | 1
Use s = ut + at2 vertically. H is the height above the ground.
2
Allow their V and θ for the M mark.
AB ( = 12 – 7.95) = 4.05 m | A1 | Allow AB = 4.06
Total: | 2
\includegraphics{figure_1}

A small ball $B$ is projected from a point $O$ on horizontal ground towards a point $A$ 12 m above the ground. 0.9 s after projection $B$ has travelled a horizontal distance of 20 m and is vertically below $A$ (see diagram).

\begin{enumerate}[label=(\roman*)]
\item Find the angle and the speed of projection of $B$. [4]

\item Calculate the distance $AB$ when $B$ is vertically below $A$. [2]
\end{enumerate}

\hfill \mbox{\textit{CAIE M2 2018 Q1 [6]}}