Properties of Magnets and Speaker Vibrations

What is the property of a magnet that allows it to attract certain materials?

• Electricity

• Friction

• Gravity

• Magnetism

How does the Earth's magnetic field affect a compass needle?

• The Earth's magnetic field causes the compass needle to align itself with the north-south direction.

• The Earth's magnetic field causes the compass needle to spin in circles

• The Earth's magnetic field has no effect on a compass needle

• The Earth's magnetic field causes the compass needle to point towards the east-west direction

Explain the difference between a permanent magnet and an electromagnet.

• A permanent magnet loses its magnetism when an electric current flows through it, while an electromagnet only becomes magnetic when an electric current flows through it.

• A permanent magnet is only magnetic when an electric current flows through it, while an electromagnet retains its magnetism without the need for an external current.

• A permanent magnet is made of non-magnetic materials, while an electromagnet is made of magnetic materials.

• A permanent magnet retains its magnetism without the need for an external current, while an electromagnet only becomes magnetic when an electric current flows through it.

What is the role of the diaphragm in a speaker's vibration?

• Control the volume of the speaker

• Convert electrical signals into sound waves

• Produce the electrical signals

• Amplify the sound waves

How does the frequency of an audio signal affect the vibration of a speaker?

• The frequency of the audio signal determines the rate at which the speaker vibrates.

• Lower frequency audio signals cause the speaker to vibrate faster.

• Higher frequency audio signals cause the speaker to vibrate slower.

• The frequency of the audio signal has no effect on the vibration of the speaker.

Describe the process of how a speaker converts electrical signals into sound waves.

• The speaker converts electrical signals into sound waves by using a series of mirrors to reflect the signals and create vibrations in the air.

• The speaker converts electrical signals into sound waves by using a network of tubes to amplify the signals and produce vibrations in the diaphragm.

• The speaker converts electrical signals into sound waves by using a set of gears to transmit the signals and generate vibrations in the air.

• The speaker converts electrical signals into sound waves by using a voice coil and a permanent magnet to create vibrations in the diaphragm.

What is the significance of the magnet in a speaker's construction?

• It creates a magnetic field that interacts with the electrical current in the voice coil.

• It helps to amplify the sound waves

• It provides a source of power for the speaker

• It is purely decorative and serves no functional purpose

Explain how the polarity of a magnet affects its interaction with other magnets.

• The polarity of a magnet has no effect on its interaction with other magnets

• The polarity of a magnet affects its interaction with other magnets by changing its color

• The polarity of a magnet affects its interaction with other magnets by either attracting or repelling them.

• The polarity of a magnet affects its interaction with other magnets by changing its weight

What are the factors that affect the strength of a magnet's magnetic field?

• Material, shape, size, and presence of other magnetic fields

• Color, weight, and temperature

• Age, flexibility, and smell

• Sound, texture, and density

How does the vibration of a speaker produce sound waves?

• The vibration of a speaker produces sound waves by attracting metal objects

• The vibration of a speaker produces sound waves by generating heat in the air

• The vibration of a speaker produces sound waves by emitting light energy

• The vibration of a speaker produces sound waves by creating vibrations in the air.