Moderate -0.3 This is a straightforward vector resolution problem requiring students to resolve four forces into components, sum them, and find the magnitude and direction of the resultant. While it involves multiple forces and some calculation, it's a standard textbook exercise testing routine application of component methods with no conceptual challenges or novel problem-solving required.
\includegraphics{figure_2}
Coplanar forces of magnitudes \(60\text{N}\), \(20\text{N}\), \(16\text{N}\) and \(14\text{N}\) act at a point in the directions shown in the diagram.
Find the magnitude and direction of the resultant force. [6]
Attempt to solve for 𝜃 or 𝛼; one missing term in total
R = 33.6 N
Direction is 64.8° above the 14 N force
or 25.2° above the negative 𝑥-axis
or 25.2° left of the 60 N force
or bearing 335°
Answer
Marks
Guidance
or 115° anticlockwise from the positive x-axis
A1
Both correct.
OE; allow 64.9, 25.1
Giving an angle only is insufficient.
Direction may be seen on a diagram, with minimum of arrow
on resultant.
Arrows on both components only is A0 as it doesn’t show the
direction of the resultant.
However the direction is stated, it must be able to be drawn
uniquely.
6
Answer
Marks
Guidance
Question
Answer
Marks
Question 2:
2 | Resolving either direction | M1 | 3 terms; allow sign errors and allow sin/cos mix
X 20cos601416cos50 14.2846 | A1
Y 6020sin6016sin50 30.42278 | A1
R 14.28462 30.422782 | M1 | Attempt to solve for R; one missing term in total
30.42278
tan1 tan12.1297
14.2846
14.2846
OR tan1 tan10.4596
30.42278 | M1 | Attempt to solve for 𝜃 or 𝛼; one missing term in total
R = 33.6 N
Direction is 64.8° above the 14 N force
or 25.2° above the negative 𝑥-axis
or 25.2° left of the 60 N force
or bearing 335°
or 115° anticlockwise from the positive x-axis | A1 | Both correct.
OE; allow 64.9, 25.1
Giving an angle only is insufficient.
Direction may be seen on a diagram, with minimum of arrow
on resultant.
Arrows on both components only is A0 as it doesn’t show the
direction of the resultant.
However the direction is stated, it must be able to be drawn
uniquely.
6
Question | Answer | Marks | Guidance
\includegraphics{figure_2}
Coplanar forces of magnitudes $60\text{N}$, $20\text{N}$, $16\text{N}$ and $14\text{N}$ act at a point in the directions shown in the diagram.
Find the magnitude and direction of the resultant force. [6]
\hfill \mbox{\textit{CAIE M1 2022 Q2 [6]}}