WJEC Further Unit 3 2023 June — Question 4

Exam BoardWJEC
ModuleFurther Unit 3 (Further Unit 3)
Year2023
SessionJune
TopicWork, energy and Power 1

4. Geraint is a cyclist competing in a race along the Taff Trail. The Taff Trail is a track that runs from Cardiff Bay to Brecon. The chart below shows the altitude (height above sea level) along the route. \begin{figure}[h]
\captionsetup{labelformat=empty} \caption{Altitude Chart of the Taff Trail} \includegraphics[alt={},max width=\textwidth]{b6b77d92-acb6-4cc3-8328-1899ed4a87cd-5_620_1701_632_191}
\end{figure} Geraint starts from rest at Cardiff Bay and has a speed of \(10 \mathrm {~ms} ^ { - 1 }\) when he crosses the finish line in Brecon. Geraint and his bike have a total mass of 80 kg . The resistance to motion may be modelled by a constant force of magnitude 16 N .
  1. Given that 1440 kJ of energy is used in overcoming resistances during the race,
    1. find the length of the track,
    2. calculate the work done by Geraint.
  2. The steepest section of the track may be modelled as a slope inclined at an angle \(\alpha\) to the horizontal, where \(\sin \alpha = \frac { 2 } { 7 }\).
    \includegraphics[max width=\textwidth, alt={}, center]{b6b77d92-acb6-4cc3-8328-1899ed4a87cd-5_513_844_1987_607} Geraint is capable of producing a maximum power of 250 W . Find the maximum speed that Geraint can attain whilst travelling on this section of the track.