Q8 · 2020 · Paper 2Simple familiar4 marks
QUESTION 8 (4 marks)
The diagram shows an object sliding down a frictionless inclined plane.
The graph shows the velocity of the object measured at various times.
Determine the angle of incline, , of the inclined plane. Show your working.
WORKED SOLUTION
4 marksQCAA guide · typeset solution
ANSWER
See worked solution below.
Worked solution
Gradient of the graph = 6 m s–2 = acceleration
The component of the acceleration due to gravity down
the inclined plane is gsin 𝜃𝜃
Therefore
gsin 𝜃𝜃 = 6
𝜃𝜃𝑖𝑖 = sin–1(6/9.8) = 38°
• arrives at a value for the gradient [1 mark]
• indicates an understanding of how the acceleration
of the object is represented by the gradient of the
graph [1 mark]
• provides pertinent mathematical operation/s
correctly performed using the gradient value
[1 mark]
• determines angle [1 mark]
One QCAA sample method typeset for web; criterion wording is adapted from the official marking guide.
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Compare your working with the guide above.