Edexcel M1 — Question 5 11 marks

Exam BoardEdexcel
ModuleM1 (Mechanics 1)
Marks11
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicMomentum and Collisions
TypePile-driver or hammer impact
DifficultyStandard +0.3 This is a straightforward multi-part mechanics problem requiring standard application of SUVAT equations, conservation of momentum, and work-energy principles. All steps are routine M1 techniques with no novel problem-solving required, making it slightly easier than average.
Spec3.02d Constant acceleration: SUVAT formulae6.03b Conservation of momentum: 1D two particles6.03f Impulse-momentum: relation

5. A sledgehammer of mass 12 kg is being used to drive a wooden post of mass 4 kg into the ground. A labourer moves the sledgehammer from rest at a point 0.5 m vertically above the post with constant acceleration \(16 \mathrm {~m} \mathrm {~s} ^ { - 2 }\) directed towards the post.
  1. Find the velocity with which the sledgehammer hits the post. When the sledgehammer hits the post, they both move together with common speed, \(V\).
  2. Show that \(V = 3 \mathrm {~ms} ^ { - 1 }\). As the sledgehammer hits the post, the labourer relaxes his grip and applies no further force. The sledgehammer and post are brought to rest by the action of a resistive force from the ground of magnitude 1500 N .
  3. Find, in centimetres, the total distance that the sledgehammer and the post travel together before coming to rest.

Question 5:
Part (a)
AnswerMarks Guidance
Answer/WorkingMarks Guidance
\(u=0\), \(s=0.5\), \(a=16\), use \(v^2 = u^2 + 2as\)M1
\(v^2 = 0 + 2(16)(0.5) \therefore v = 4\) ms\(^{-1}\)M1 A1
Part (b)
AnswerMarks Guidance
Answer/WorkingMarks Guidance
Cons. of mom. \(12(4) = (12+4)V\)M1
\(48 = 16V \therefore V = 3\) ms\(^{-1}\)A1
Part (c)
AnswerMarks Guidance
Answer/WorkingMarks Guidance
Eqn. of motion: \(16g - 1500 = 16a\)M1 A1
\(\therefore a = -83.95\)A1
Use with \(u=3\), \(v=0\) in \(v^2 = u^2 + 2as\)M1
\(v^2 = 3^2 - 167.9s\) giving \(s = 0.054\) m \(= 5.4\) cmM1 A1 (11)
## Question 5:

### Part (a)
| Answer/Working | Marks | Guidance |
|---|---|---|
| $u=0$, $s=0.5$, $a=16$, use $v^2 = u^2 + 2as$ | M1 | |
| $v^2 = 0 + 2(16)(0.5) \therefore v = 4$ ms$^{-1}$ | M1 A1 | |

### Part (b)
| Answer/Working | Marks | Guidance |
|---|---|---|
| Cons. of mom. $12(4) = (12+4)V$ | M1 | |
| $48 = 16V \therefore V = 3$ ms$^{-1}$ | A1 | |

### Part (c)
| Answer/Working | Marks | Guidance |
|---|---|---|
| Eqn. of motion: $16g - 1500 = 16a$ | M1 A1 | |
| $\therefore a = -83.95$ | A1 | |
| Use with $u=3$, $v=0$ in $v^2 = u^2 + 2as$ | M1 | |
| $v^2 = 3^2 - 167.9s$ giving $s = 0.054$ m $= 5.4$ cm | M1 A1 | **(11)** |

---
5. A sledgehammer of mass 12 kg is being used to drive a wooden post of mass 4 kg into the ground. A labourer moves the sledgehammer from rest at a point 0.5 m vertically above the post with constant acceleration $16 \mathrm {~m} \mathrm {~s} ^ { - 2 }$ directed towards the post.
\begin{enumerate}[label=(\alph*)]
\item Find the velocity with which the sledgehammer hits the post.

When the sledgehammer hits the post, they both move together with common speed, $V$.
\item Show that $V = 3 \mathrm {~ms} ^ { - 1 }$.

As the sledgehammer hits the post, the labourer relaxes his grip and applies no further force. The sledgehammer and post are brought to rest by the action of a resistive force from the ground of magnitude 1500 N .
\item Find, in centimetres, the total distance that the sledgehammer and the post travel together before coming to rest.
\end{enumerate}

\hfill \mbox{\textit{Edexcel M1  Q5 [11]}}