16

Question 1

What is the primary function of a compass?

Answer 1

To indicate geographic North using a small magnet that points to magnetic South

The compass relies on Earth’s magnetic field to function.

Question 2

What are the two poles of Earth in terms of magnetism?

Answer 2

Magnetic South and Magnetic North

Magnetic South is the south-seeking pole of the compass.

Question 3

What happens to Earth’s magnetic poles over time?

Answer 3

They can be reversed

This phenomenon is known as geomagnetic reversal.

Question 4

What produces a magnetic field in an electromagnet?

Answer 4

An electric current flowing through a coil of wire around a core

The core is usually made of iron to enhance the magnetic field.

Question 5

How can the strength of an electromagnet be increased?

Answer 5

By:
* Adding more coils around the core
* Increasing the size of the iron core
* Increasing the electric current

Each of these methods enhances the magnetic field produced.

Question 6

What occurs when the battery in an electromagnet is flipped?

Answer 6

The North and South poles reverse

This is due to the change in direction of the electric current.

Question 7

What is the function of an electric bell?

Answer 7

To produce sound by attracting a metal arm to strike a gong

The metal arm is attracted by the electromagnet when switched on.

Question 8

How does an electric motor maintain consistent force direction?

Answer 8

By swapping the connections every half turn

This ensures that the forces always act in the same direction, regardless of the current direction.

Question 9

Fill in the blank: The magnetic field is produced when an electric current flows through a _______.

Answer 9

coil of wire

The coil is often wrapped around a magnetic core.

Question 10

True or False: The direction of the current in an electric motor remains constant.

Answer 10

False

The current direction swaps every half turn in an electric motor.