Question

which of the following is true of electromagnetic waves? answer options: select one of four they can travel through a vacuum. they cant be refracted by any known material. they travel at approximately 300 m/s in ideal conditions. they follow the principle velocity = wavelength + frequency.

Explanation:

• Analyze Option 1: Electromagnetic waves (like light) can travel through a vacuum (space is a vacuum, and light from stars reaches us).
• Analyze Option 2: Electromagnetic waves can be refracted (e.g., light refracts in water or glass), so this is false.
• Analyze Option 3: The speed of electromagnetic waves in a vacuum is approximately \( 3\times10^8 \, \text{m/s} \) (300,000,000 m/s), not 300 m/s, so this is false.
• Analyze Option 4: The correct formula for wave velocity is \( v = \lambda \times f \) (velocity = wavelength × frequency), not wavelength + frequency, so this is false.

Answer:

A. They can travel through a vacuum.