The electromagnetic spectrum and its uses
Grade 11 Science Worksheet - Building Confidence
Circle the best answer, or write your answer on the line.
Ari tunes a radio to 100 MHz. What is the wavelength of the signal?
Esme listens to an AM station at 600 kHz. What is the wavelength of the signal?
Which list orders these waves from lowest to highest photon energy: UV, radio, X-rays, infrared, visible, Jun?
- Radio, visible, infrared, UV, X-rays
- X-rays, UV, visible, infrared, radio
- Infrared, radio, visible, X-rays, UV
- Radio, infrared, visible, UV, X-rays
Green light is 550 nm and red light is 700 nm. Which has the higher frequency, and about what is it, Kira?
- Both the same, since light has one speed
- Red, about 4.3 × 10¹⁴ Hz, since longer waves have higher frequency
- Green, about 5.5 × 10¹⁴ Hz
- Green, about 5.5 × 10¹¹ Hz
The microwave band runs from about 1 mm to 30 cm. Where does a 12 cm wave fall, and what is its frequency, Luz?
- Inside the microwave band, at about 2.5 GHz
- In the radio band, since 12 cm is longer than 1 mm
- Inside the microwave band, at about 2.5 MHz
- Inside the microwave band, at about 36 MHz
Why can ultraviolet sunburn skin when visible light of the same brightness does not, Noah?
- UV is a hotter kind of light than visible light is
- UV travels faster than visible light, so it hits harder
- Each UV photon carries more energy, enough to damage skin cells
- UV has longer wavelengths, so each photon carries more energy
Why can Wi-Fi pass through a wall, but a TV remote's infrared cannot, Pia?
- Walls let 12 cm radio waves through but block infrared
- Radio waves travel faster than infrared, so they get through
- Infrared is too bright to pass through a wall
- Wi-Fi has more energy per photon than infrared
A radio signal and a flash of light leave the Moon together, 384,400 km away. Which arrives first, Ren?
- The radio signal, since its wavelength is longer
- They arrive together, after about 1.3 minutes
- They arrive together, after about 1.3 s
- The light, since its frequency is higher
In a vacuum, a wave's frequency doubles. What happens to its wavelength, Tala?
- It stays the same, because it is the same kind of wave
- It quadruples, because λ goes as f²
- It halves, because the speed stays fixed
- It doubles, because the wave speeds up
Wi-Fi works at 2.4 GHz and at 5 GHz. Which has the longer wavelength, and by about how much, Zee?
- 2.4 GHz, by a factor of about 2
- 5 GHz, by a factor of about 2
- Neither: they both travel at c
- 2.4 GHz, by a factor of about 2.4