science review

What is a key difference between electromagnetic waves and mechanical waves?

• Electromagnetic waves do not require a medium to propagate, while mechanical waves do.

• Electromagnetic waves require a medium to propagate, while mechanical waves do not.

• Both electromagnetic and mechanical waves require a medium to propagate.

• Neither electromagnetic nor mechanical waves require a medium to propagate.

Who first theorized the concept of electromagnetic waves?

• James Clerk Maxwell

• Heinrich Hertz

• Albert Einstein

• Isaac Newton

What is the relationship between the wavelength and energy of an electromagnetic wave?

• As the wavelength shortens, the energy increases.

• As the wavelength shortens, the energy decreases.

• Wavelength and energy are not related.

• As the wavelength increases, the energy increases.

What is the frequency range of sound waves audible to humans?

• 20 to 20,000 Hz

• 10 to 10,000 Hz

• 50 to 50,000 Hz

• 100 to 100,000 Hz

What technology uses sound waves to determine the distance and speed of objects underwater?

• Sonar

• Radar

• Lidar

• Ultrasound

How do electromagnetic waves differ from mechanical waves?

• A) Electromagnetic waves require a medium, while mechanical waves do not

• B) Mechanical waves can travel through space, but electromagnetic waves cannot

• C) Electromagnetic waves do not require a medium, while mechanical waves do

• 
  D) Both types of waves require a medium

What happens to the energy of an electromagnetic wave as its wavelength decreases?

• A) The energy increases

• B) The energy decreases

• C) The energy remains the same

• D) The energy becomes negative

What are ultrasonic waves used for?

• A) Cooking food

• B) Medical imaging and industrial cleaning

• C) Producing electricity

• D) Sending radio signals