L.2 Magnetism & Electromagnetism

Practice Worksheet — name: ______________________ date: ____________

Section A — Multiple choice

A1. Which of the following will increase the strength of an electromagnet?

A Decreasing the current
B Using fewer coils
C Inserting an iron core
D Using a wooden core

A2. What rule is used to determine the direction of the force on a current‑carrying conductor in a magnetic field?

A Ohm’s law
B Right‑hand grip rule
C Fleming’s left‑hand rule
D Hooke’s law

Section B — Short answer

B1. Describe how you could make a simple electromagnet.

B2. Explain why an alternating current in a coil is necessary for a transformer to work.

Answer key

For worked explanations, interactive practice and more free resources, visit www.newtonine.com

Section A

A1: Inserting an iron core

A2: Fleming’s left‑hand rule

Section B

B1: Wrap a coil of insulated wire around an iron nail, connect the ends to a battery. When current flows, the nail becomes magnetised.

B2: A changing current produces a changing magnetic field, which induces a voltage in a secondary coil via electromagnetic induction. A steady DC current would not produce a changing field, so no voltage would be induced.