Skip to content
MathsGenie logo
Open app

Course home

  1. A Level
  2. Maths WJEC
  3. Question bank

Forces and Friction

EasyMediumHard
12
Question 1

An anchoring force P\mathbf{P}P of magnitude 120 N is applied to a structural joint. The force acts in the third quadrant relative to the standard unit vectors i\mathbf{i}i (pointing right) and j\mathbf{j}j (pointing upwards). The direction of the force makes an angle of 25∘ 25^\circ\,25∘ with the negative yyy-axis.

The force can be expressed as a vector [PxPy] N\begin{bmatrix} P_x \\ P_y \end{bmatrix} \text{ N}[Px​Py​​] N.

Find the correct expression for PyP_yPy​.

Py=120cos⁡25∘P_y = 120 \cos 25^\circPy​=120cos25∘

Py=−120sin⁡25∘P_y = -120 \sin 25^\circPy​=−120sin25∘

Py=−120cos⁡25∘P_y = -120 \cos 25^\circPy​=−120cos25∘

Py=120sin⁡25∘P_y = 120 \sin 25^\circPy​=120sin25∘

[3]

Forces and Friction Questions

  1. A Level
  2. /Maths
  3. /Forces and Friction