Q13 · 2025 · Technology-freeSimple familiar5 marks
QUESTION 13 (5 marks)
The velocity (m s) of a 3 kg object moving in a straight line is given by
where is its position (m) from the origin.
a)[2 marks]
Determine the momentum (kg m s) of the object when it is at the origin.
b)[3 marks]
Determine the acceleration (m s) of the object when it is at the origin.
WORKED SOLUTION
5 marksQCAA guide · typeset solution
ANSWER
a) kg m s. b) m s.
Worked solution
a) At ,
Thus the momentum is
b)
Using ,
At ,
correctly determines the velocity of the object at the origin
determines the momentum of the object at the origin
correctly determines the expression for
determines an expression for acceleration using
determines the acceleration of the object at the origin
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