Unit 3 Practice

What are the two types of broadcast radio?

• AM and FM

• AM and PM

• FM and PM

• AM and EM

Answer explanation

The two main types of broadcast radio are AM (Amplitude Modulation) and FM (Frequency Modulation). AM is known for its longer range, while FM offers better sound quality, making 'AM and FM' the correct answer.

Tags

8.PS4.3

Why do AM radio waves travel further at night?

• Because the ionosphere disappears at night

• Because FM radio waves bounce off the ionosphere at night

• Because the sun gives off more radiation at night

• Because the wavelength of AM radio waves is longer

Answer explanation

AM radio waves travel further at night primarily because they have longer wavelengths. This allows them to diffract around obstacles and reflect off the ionosphere, enhancing their range compared to shorter FM waves.

Tags

8.PS4.3

Why can FM radio only be picked up within line-of-sight of the broadcast tower?

• Because FM radio waves are absorbed by the ionosphere

• Because FM radio waves are too short to travel long distances

• Because FM radio waves are blocked by buildings and obstacles

• Because FM radio waves are only transmitted during the day

Answer explanation

FM radio waves have shorter wavelengths, which limits their ability to diffract around obstacles. This results in a line-of-sight requirement for effective reception, making them less capable of traveling long distances.

Tags

8.PS4.3

What is the main advantage of FM radio over AM radio?

• Higher quality transmission

• Longer range

• Lower frequency

• Better nighttime broadcasting

Answer explanation

The main advantage of FM radio over AM radio is its higher quality transmission. FM signals are less susceptible to noise and interference, resulting in clearer sound quality, especially for music and high-fidelity broadcasts.

Tags

8.PS4.3

What is the main disadvantage of AM radio in terms of signal reception?

• AM radio is more susceptible to interference

• AM radio has a shorter range

• AM radio has a lower frequency

• AM radio has a narrower bandwidth

Answer explanation

The main disadvantage of AM radio is its susceptibility to interference from electrical devices and atmospheric conditions, which can distort the signal and affect reception quality.

Tags

8.PS4.3

What is the primary factor that determines the range of an FM radio station?

• The height of the broadcast tower

• The frequency of the station

• The power of the transmitter

• The location of the listener

Answer explanation

The height of the broadcast tower is crucial for FM radio range, as it affects line-of-sight transmission and reduces obstacles. Taller towers can transmit signals further, making this the primary factor in determining range.

Tags

8.PS4.3

Which type of electromagnetic radiation has the shortest wavelength?

• Radio Waves

• Visible Light

• Microwaves

• Gamma Rays

Answer explanation

Gamma rays have the shortest wavelength in the electromagnetic spectrum, making them the correct answer. In contrast, radio waves, visible light, and microwaves have longer wavelengths.

Tags

NGSS.HS-PS4-1

Which type of electromagnetic radiation has the shortest wavelength?

• Radio Waves

• Visible Light

• Microwaves

• Gamma Rays

Answer explanation

Gamma rays have the shortest wavelength in the electromagnetic spectrum, making them the correct answer. In contrast, radio waves, visible light, and microwaves have longer wavelengths.

Tags

NGSS.HS-PS4-1

Which type of visible light has the highest energy?

• Red

• Yellow

• Green

• Violet

Answer explanation

Violet light has the highest energy among visible light colors due to its shorter wavelength. In the visible spectrum, energy increases as wavelength decreases, making violet the most energetic color.

Tags

NGSS.HS-PS4-1

NGSS.HS-PS4-3

Which type of radiation has a frequency closest to 10⁵?

• Radio

• Infrared

• Ultraviolet

• X-Ray

Answer explanation

Radio waves have frequencies in the range of 10^4 to 10^9 Hz, making them the type of radiation closest to 10^5 Hz. Infrared, ultraviolet, and X-rays have much higher frequencies, thus the correct answer is Radio.

Tags

NGSS.HS-PS4-1