13 Electromagnetic Spectrum 2023

Where do all types of electromagnetic waves travel at the same speed?

• air

• a vacuum

• glass

• water

Where do all the waves travel at the same speed?

• in a vacuum

• in diamond

• in glass

• in water

The diagram shows the electromagnetic spectrum.

Which types of wave are E, F and G?

Suggest why a Bluetooth headset only works well over short distances.

• Because Bluetooth technology is designed for short-range communication

• Because Bluetooth headsets have limited battery life

• Because Bluetooth headsets are not compatible with all devices

• Because Bluetooth headsets are expensive

Which statement is correct?

• A remote controller emits microwave radiation.

• A remote controller emits infrared radiation.

• A remote controller emits ultrasound.

• A remote controller emits ultraviolet radiation.

The two devices shown use different types of electromagnetic waves. Which types of waves are used in these devices?

• medical scanning - ultraviolet,

  remote controller - infrared

• medical scanning - ultraviolet,

  remote controller - microwaves

• medical scanning - X-rays,

  remote controller - infrared

• medical scanning - X-rays,

  remote controller - microwaves

Which row matches a region of the electromagnetic spectrum to one of its uses?

Visible light has wavelengths in the range 4.0 × 10⁻⁷ m to 7.0 × 10⁻⁷ m. What is the range of the frequencies of visible light?

• 0.12 Hz to 0.21 Hz

• 120 Hz to 210 Hz

• 4.3 × 10¹¹ Hz to 7.5 × 10¹¹ Hz

• 4.3 × 10¹⁴ Hz to 7.5 × 10¹⁴ Hz

A radio station broadcasts a signal with a frequency of 89 MHz. What is the wavelength of this signal?

• 3.7 μm

• 3.4 m

• 3.7 km

• 3.4 Mm

A student writes four statements matching a communication system to the region of the electromagnetic spectrum that it uses to transmit signals. Which statement is correct?

• Wireless internet uses visible wavelengths.

• Mobile phones use X-rays.

• Cable television uses infrared wavelengths.

• Bluetooth uses ultraviolet wavelengths.