Six original Cambridge-style questions on the magnetic effect of a current: the field patterns of a wire and a coil, reversing the current, making the field stronger, and the electromagnet in real life.
Describe the shape of the magnetic field around a long straight wire carrying a current.
Describe the magnetic field produced by a current in a solenoid (a long coil).
A plotting compass is placed near a wire carrying a current and the needle points in a certain direction. State what happens to the needle if the current is reversed, and why.
State three ways to increase the strength of the magnetic field of a solenoid.
A scrapyard crane uses an electromagnet to lift cars. Explain why an electromagnet is used instead of a permanent magnet.
A coil with a soft-iron core is connected to a battery. State what happens to the magnetism of the core when the current is switched off, and why a soft-iron core is chosen rather than a steel one.
Mark this once you have attempted all six and checked your working. It records a Practiced badge on the topic and adds a one-time bonus. Revealing the solutions alone does not count.