WJEC Unit 2 2018 June — Question 10 7 marks

Exam BoardWJEC
ModuleUnit 2 (Unit 2)
Year2018
SessionJune
Marks7
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicForces, equilibrium and resultants
TypeLift with occupant problems
DifficultyModerate -0.8 This is a straightforward mechanics problem requiring application of Newton's second law to two connected bodies. Part (a) involves a single F=ma calculation with total mass, part (b) is immediate interpretation, and part (c) applies F=ma again to the person alone. All steps are routine with no conceptual subtlety—easier than average A-level questions which typically require more problem-solving or integration of multiple techniques.
Spec3.03c Newton's second law: F=ma one dimension3.03d Newton's second law: 2D vectors3.03f Weight: W=mg

A person, of mass 68 kg, stands in a lift which is moving upwards with constant acceleration. The lift is of mass 770 kg and the tension in the lift cable is 8000 N.
  1. Determine the acceleration of the lift, giving your answer correct to two decimal places. [3]
  2. State whether the lift is getting faster, staying at the same speed or slowing down. [1]
  3. Calculate the magnitude of the reaction of the floor of the lift on the person. [3]

A person, of mass 68 kg, stands in a lift which is moving upwards with constant acceleration. The lift is of mass 770 kg and the tension in the lift cable is 8000 N.

\begin{enumerate}[label=(\alph*)]
\item Determine the acceleration of the lift, giving your answer correct to two decimal places. [3]

\item State whether the lift is getting faster, staying at the same speed or slowing down. [1]

\item Calculate the magnitude of the reaction of the floor of the lift on the person. [3]
\end{enumerate}

\hfill \mbox{\textit{WJEC Unit 2 2018 Q10 [7]}}