| Exam Board | Edexcel |
|---|---|
| Module | M1 (Mechanics 1) |
| Year | 2005 |
| Session | June |
| Marks | 10 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Moments |
| Type | Uniform beam on two supports |
| Difficulty | Standard +0.3 This is a standard M1 moments question requiring taking moments about a point and using equilibrium conditions. Part (a) is straightforward (moments about A), while part (b) requires setting up two equations (equal reactions and moment equilibrium) and solving simultaneously. The 7 marks indicate multiple steps, but the techniques are routine textbook applications with no novel insight required—slightly easier than average A-level difficulty. |
| Spec | 3.04a Calculate moments: about a point3.04b Equilibrium: zero resultant moment and force3.04c Use moments: beams, ladders, static problems |
| Answer | Marks |
|---|---|
| 6 | R |
| Answer | Marks |
|---|---|
| Sub for S and solve for x: x = 7/8 or 0.875 or 0.88 m | M1 A1 |
Question 6:
6 | R
(a) M(A): 12g x 1.5 = R x 2
12g R = 9g or 88.2 N
(b)
S S R(↑) 2S = 48g + 12g
x
48g 12g S = 30g
M(A): S x 2 = 12g x 1.5 + 48g x x
Sub for S and solve for x: x = 7/8 or 0.875 or 0.88 m | M1 A1
A1
(3)
M1 A1
M1 A2,1,0
↓↓
M1 A1
(7)\includegraphics{figure_3}
A uniform beam $AB$ has mass 12 kg and length 3 m. The beam rests in equilibrium in a horizontal position, resting on two smooth supports. One support is at the end $A$, the other at a point $C$ on the beam, where $BC = 1$ m, as shown in Figure 3. The beam is modelled as a uniform rod.
\begin{enumerate}[label=(\alph*)]
\item Find the reaction on the beam at $C$. [3]
\end{enumerate}
A woman of mass 48 kg stands on the beam at the point $D$. The beam remains in equilibrium. The reactions on the beam at $A$ and $C$ are now equal.
\begin{enumerate}[label=(\alph*)]
\setcounter{enumii}{1}
\item Find the distance $AD$. [7]
\end{enumerate}
\hfill \mbox{\textit{Edexcel M1 2005 Q6 [10]}}