Generated with Monsha

Save this resource to edit, expand, or export it, or create more resources for free.

Electromagnetism Reading Comprehension

Reading Comprehension Questions
Grade 12
English

Electromagnetism Reading Comprehension

Electromagnetism is a phenomenon where electric currents produce their own magnetic fields. When current flows through a straight wire, it generates a magnetic field that forms concentric circles around the wire, with the field being strongest near the wire. The direction of this magnetic field depends on the direction of the current and can be determined using the right hand rule: if you point your right thumb in the direction of the current, your fingers curl in the direction of the magnetic field.
If the current in the wire is reversed, the direction of the magnetic field also reverses. When a wire is shaped into a flat coil, the magnetic fields from each side interact and combine, forming a single magnetic field that runs straight through the center of the coil. Adding more turns to the coil creates a solenoid, which produces a strong and uniform magnetic field inside. Outside the solenoid, the field resembles that of a bar magnet, with a north and south pole.
An electromagnet is created when a current flows through a solenoid. This magnetism can be switched on or off by controlling the current. The direction of the magnetic field can also be reversed by reversing the current. However, a small electromagnet produces a weak magnetic field. The strength of an electromagnet can be increased in four ways: increasing the current, increasing the number of turns in the coil, decreasing the length of the coil while keeping the number of turns the same, and inserting an iron core inside the solenoid. Iron becomes an induced magnet when the current is on and loses its magnetism when the current is off.

Essential Questions

  1. Why is the right hand rule important when studying electromagnetism?

Multiple Choice Questions

  1. Which of the following does NOT increase the strength of an electromagnet?
a) Increasing the current through the solenoid b) Adding more turns to the coil c) Using a wooden core inside the solenoid d) Decreasing the length of the solenoid while keeping the number of turns the same