Physics 9702/52 — May/June 2023

Two coils, P and Q, are placed close to each other, as shown in Fig. 1.1.

A resistor of resistance $R$ is connected in series with coil P.

A changing magnetic flux of frequency $f$ in coil P causes an electromotive force (e.m.f.) $E$ to be induced across the terminals of coil Q.

It is suggested that $E$ is related to $R$ by the relationship

$$E = 2\pi fM \left( \frac{V}{R + k} \right)$$

where $V$ is the potential difference across the resistor and coil P, and $k$ and $M$ are constants.

Plan a laboratory experiment to test the relationship between $E$ and $R$.

Draw a diagram showing the arrangement of your equipment.

Explain how the results could be used to determine values for $k$ and $M$.

In your plan you should include:

• the procedure to be followed
• the measurements to be taken
• the control of variables
• the analysis of the data
• any safety precautions to be taken.