Applications of electromagnetic waves — practice questions

Question 1 · difficulty L1 · recall

Microwaves are widely used in

• A. bone imaging by high penetration only
• B. sterilisation using ionising gamma photons only
• C. radar and satellite communication
• D. ordinary AM broadcasting at kilometre wavelengths only

Question 2 · difficulty L1 · understanding

Infrared radiation is strongly associated with

• A. nuclear radiotherapy
• B. crystal diffraction at atomic spacing
• C. AM radio transmission
• D. thermal imaging and remote controls

Question 3 · difficulty L2 · understanding

Ultraviolet radiation is commonly used for

• A. sterilisation and fluorescence applications
• B. long-distance AM radio
• C. cooking by molecular rotation only
• D. deep-tissue gamma radiotherapy

Question 4 · difficulty L2 · application

X-rays are especially useful for

• A. radio broadcasting
• B. medical radiography and crystal-structure studies
• C. TV remote controls
• D. heating food in microwave ovens

Question 5 · difficulty L3 · application

Gamma rays are used in

• A. FM radio transmission
• B. night-vision remote controls
• C. cancer radiotherapy and sterilisation
• D. ordinary optical fibre communication as visible light only

Question 6 · difficulty L3 · application

Radio waves are especially suitable for

• A. viewing bone fractures directly
• B. sterilising surgical instruments by ionisation
• C. measuring atomic lattice spacing by diffraction
• D. broadcasting and long-range communication

Question 7 · difficulty L4 · analysis

Which radiation is most directly associated with night-vision thermal cameras?

• A. Infrared
• B. Ultraviolet
• C. X-ray
• D. Gamma

Question 8 · difficulty L4 · analysis

A security scanner designed to image dense luggage contents using highly penetrating photons commonly uses

• A. long radio waves
• B. X-rays
• C. infrared only
• D. visible red light only

Question 9 · difficulty L5 · analysis

Why are microwaves suitable for satellite communication through the atmosphere?

• A. They require a solid conducting medium between satellite and Earth
• B. They always reflect completely from the ionosphere
• C. Selected microwave bands can pass through the atmosphere and support narrow directional beams
• D. Their speed in vacuum is greater than c

Question 10 · difficulty L5 · analysis

A hospital needs radiation for imaging broken bones and a different radiation for certain cancer treatments. A standard pairing is

• A. Radio waves for imaging and infrared for treatment
• B. Microwaves for imaging and visible light for treatment
• C. Ultraviolet for bone imaging and radio waves for treatment
• D. X-rays for imaging and gamma rays for treatment