Physics (AS & A Level) · May / June 2018 · Paper 13 · Question 4

What will reduce the systematic errors when taking a measurement?

1. Aadjusting the needle on a voltmeter so that it reads zero when there is no potential difference across it
2. Bmeasuring the diameter of a wire at different points and taking the average
3. Creducing the parallax effects by using a marker and a mirror when measuring the amplitude of oscillation of a pendulum
4. Dtiming 20 oscillations, rather than a single oscillation, when finding the period of a pendulum

As printed in the paper