Paper 5 Planning, Analysis & Evaluation

Need to know

What you need to know

• Identify the Independent Variable (IV), Dependent Variable (DV), and variables to be kept constant.
• Draw a clear, fully labelled diagram of the experimental setup. Use standard circuit symbols where appropriate.
• Write a sequential procedure, explaining how to vary the IV over a wide range (at least 6-8 values) and how to accurately measure the DV.
• For reliability, state that you will take repeat readings of the DV at each value of the IV and calculate a mean.
• Describe the graphical analysis: linearise the given equation and state what to plot on the y-axis and x-axis to get a straight line.
• Explain how the constants in the equation are determined from the gradient and/or y-intercept of the graph.
• Include at least one significant safety precaution with a reason (e.g., 'wear safety goggles as the wire may snap under tension').

Explanation

Two halves of Paper 5

1. Q1: Diagram → procedure → variables held constant → graph to plot → how constants come from gradient/intercept.
2. Q2(b): Fill table columns including absolute uncertainties in derived quantities.
3. Q2(c)(i): Plot points with vertical error bars.
4. Q2(c)(ii–iv): LOBF + one WAL (both labelled), then large triangle for gradient/intercept; uncertainty = |best − worst|.