A student placed a magnet on top of a plastic support in a bowl of water - AQA - GCSE Physics - Question 5 - 2020 - Paper 1

When the piece of iron was placed near the fixed magnet, it was attracted to the fixed magnet. This occurs because the iron becomes magnetized and behaves like a magnet, adhering to the fixed magnet.

To plot the magnetic field around a bar magnet using a compass:

1. Place the compass near one pole of the bar magnet (north or south).
2. Observe the direction in which the compass needle points, which indicates the direction of the magnetic field.
3. Mark the position of the compass on a piece of paper.
4. Move the compass to this marked point and repeat the process, moving around the magnet until you have several points marked.
5. Connect the points with a smooth line to represent the magnetic field lines.
6. Add arrows to indicate the direction of the field, pointing from the north pole to the south pole of the magnet.

A - C - B

The elastic potential energy can be calculated using the formula:

$E_p = 0.5 imes k imes x^2$

where:

• $E_p$ is the elastic potential energy,
• $k$ is the spring constant (200 N/m), and
• $x$ is the extension (0.040 m).

Substituting the values: $E_p = 0.5 imes 200 imes (0.040)^2 = 0.16 ext{ J}$