Electromagnetic Waves: Properties, Applications, and Exam Prep

Question 1

What is the numerical value of the speed of light in a vacuum?

Accepted Answer

299,792,458 m/s

Answer

340,292 m/s

Answer

186,282 m/s

Answer

270,000 m/s

Question 2

Which SI unit is used to measure energy in electromagnetism?

Accepted Answer

Joule

Answer

Watt

Answer

Electronvolt

Answer

Tesla

Question 3

Which of the following materials is opaque to electromagnetic waves?

Accepted Answer

Metal

Answer

Glass

Answer

Wood

Answer

Concrete

Question 4

What is the term for the process by which electromagnetic waves can be concentrated and reflected?

Accepted Answer

Reflection

Answer

Refraction

Answer

Diffraction

Answer

Polarization

Question 5

Which region of the electromagnetic spectrum has the highest frequency?

Accepted Answer

Gamma rays

Answer

X-rays

Answer

Ultraviolet rays

Answer

Microwaves

Question 6

Which of the following is NOT a fundamental property of electromagnetic waves?

Accepted Answer

Have mass

Answer

Travel at the speed of light in a vacuum

Answer

Are transverse waves

Answer

Can be polarized

Question 7

What is the standard unit for measuring the wavelength of electromagnetic waves?

Accepted Answer

Meter

Answer

Hertz

Answer

Volt

Answer

Ampere

Question 8

Which type of electromagnetic wave possesses the highest energy?

Accepted Answer

Gamma rays

Answer

Radio waves

Answer

Microwaves

Answer

Infrared radiation

Question 9

What is the process by which electromagnetic waves transmit energy without transferring matter?

Accepted Answer

Radiation

Answer

Conduction

Answer

Convection

Answer

Induction

Question 10

Which property is characteristic of electromagnetic waves?

Accepted Answer

They can propagate through a vacuum.

Answer

They exhibit longitudinal vibrations.

Answer

They cannot be polarized.

Answer

They require a medium for propagation.

Question 11

The electromagnetic spectrum is arranged based on:

Accepted Answer

Increasing frequency

Answer

Decreasing wavelength

Answer

Increasing energy

Answer

Decreasing amplitude

Question 12

Which application predominantly relies on the wave-particle duality of electromagnetic waves?

Accepted Answer

Photoelectric effect

Answer

Radio communication

Answer

Microwave heating

Answer

Optical fiber transmission

Question 13

Which device is commonly used to detect electromagnetic waves?

Accepted Answer

Antenna

Answer

Microphone

Answer

Thermometer

Answer

Barometer

Question 14

The wavelength of an electromagnetic wave is inversely proportional to its:

Accepted Answer

Frequency

Answer

Amplitude

Answer

Energy

Answer

Velocity

Question 15

Which material allows electromagnetic waves to pass through it?

Accepted Answer

Glass

Answer

Metal

Answer

Wood

Answer

Water

Question 16

The energy carried by an electromagnetic wave is directly proportional to its:

Accepted Answer

Frequency

Answer

Wavelength

Answer

Amplitude

Answer

Speed

Question 17

Microwaves are characterized by:

Accepted Answer

High frequency, short wavelength

Answer

Low frequency, long wavelength

Answer

High amplitude, short wavelength

Answer

Low amplitude, long wavelength

Question 18

The phenomenon of reflection occurs when electromagnetic waves encounter a:

Accepted Answer

Boundary between two different media

Answer

Change in frequency

Answer

Change in amplitude

Answer

Change in wavelength

Question 19

State one property of electromagnetic waves that distinguishes them as a transverse wave.

Accepted Answer

They oscillate perpendicular to the direction of propagation.

Answer

They oscillate parallel to the direction of propagation.

Answer

They propagate through a vacuum.

Answer

They can be reflected and refracted.

Question 20

Which of the following equations accurately represents the relationship between the wavelength (λ), frequency (f), and speed (v) of an electromagnetic wave?

Accepted Answer

v = λf

Answer

λf = v

Answer

λ = vf

Answer

f = vλ

Question 21

In medical imaging, what is the primary application of X-rays?

Accepted Answer

Imaging bones and tissues

Answer

Treating cancer

Answer

Sterilizing medical equipment

Answer

Magnetic resonance imaging

Question 22

What phenomenon describes the bending of electromagnetic waves around an obstacle?

Accepted Answer

Diffraction

Answer

Reflection

Answer

Refraction

Answer

Interference

Question 23

Describe a characteristic of polarized electromagnetic waves.

Accepted Answer

Vibrations occur in a single specific plane.

Answer

Vibrations occur in multiple arbitrary planes.

Answer

Vibrations have no specific plane of occurrence.

Answer

Polarized waves have high intensity.

Question 24

What is the term for the discrete unit of energy associated with electromagnetic waves?

Accepted Answer

Photon

Answer

Electron

Answer

Neutron

Answer

Quark

Question 25

The electromagnetic spectrum is categorized into different regions based on which properties?

Accepted Answer

Wavelength and frequency

Answer

Energy and intensity

Answer

Amplitude and phase

Answer

Polarization and coherence

Question 26

Which application of electromagnetic waves utilizes their ability to penetrate matter?

Accepted Answer

Medical imaging (X-rays)

Answer

Microwave heating

Answer

Radio communication

Answer

Optical fiber communication

Question 27

The wave-particle duality of electromagnetic waves implies that they can:

Accepted Answer

Behave both as waves and particles.

Answer

Only behave as particles.

Answer

Only behave as waves.

Answer

Never exhibit both wave and particle properties.

Question 28

The energy carried by an electromagnetic wave is directly proportional to its:

Accepted Answer

Frequency

Answer

Wavelength

Answer

Amplitude

Answer

Intensity

Question 29

The unit of intensity in the context of electromagnetic waves is:

Accepted Answer

Watts per square meter (W/m²)

Answer

Joules per second (J/s)

Answer

Hertz (Hz)

Answer

Meters per second (m/s)

Question 30

Which of the following is an example of interference in electromagnetic waves?

Accepted Answer

The creation of a rainbow

Answer

The bending of light through a prism

Answer

The production of sound waves by a speaker

Answer

The reflection of microwaves from a metal surface

Question 31

The blue color of the sky is primarily caused by the:

Accepted Answer

Scattering of sunlight

Answer

Reflection of sunlight

Answer

Refraction of sunlight

Answer

Diffraction of sunlight

Question 32

Which of the following technologies uses electromagnetic waves for wireless communication?

Accepted Answer

Bluetooth

Answer

Fiber optics

Answer

Magnetic resonance imaging (MRI)

Answer

Ultrasound

Question 33

When an electromagnetic wave moves from a vacuum into a material with a higher refractive index, what happens to its speed?

Accepted Answer

Decreases

Answer

Increases

Answer

Stays the same

Answer

Becomes inversely proportional to the wavelength

Question 34

How do X-rays use electromagnetic waves to create images?

Accepted Answer

X-rays penetrate the body, with denser tissues absorbing more radiation, creating an image based on varying absorption levels.

Answer

X-rays bounce off the body's surface, creating an image based on the intensity of the reflected waves.

Answer

X-rays generate a magnetic field that interacts with body tissues, forming an image.

Answer

X-rays ionize atoms in the body, forming an image based on the quantity of ions produced.

Question 35

Who is widely credited with the discovery of electromagnetic waves, and in what year was this discovery made?

Accepted Answer

James Clerk Maxwell - 1865

Answer

Albert Einstein - 1905

Answer

Michael Faraday - 1831

Answer

Heinrich Hertz - 1886

Question 36

Within the electromagnetic spectrum, which region exhibits the shortest wavelength range?

Accepted Answer

Gamma rays

Answer

Microwaves

Answer

Visible light

Answer

Radio waves

Question 37

What is the relationship between the frequency (f) and wavelength (λ) of an electromagnetic wave?

Accepted Answer

f is inversely proportional to λ

Answer

f is not related to λ

Answer

f is equal to λ

Answer

f is directly proportional to λ

Question 38

Which unit is used to measure magnetic flux density?

Accepted Answer

Tesla

Answer

Ampere

Answer

Weber

Answer

Gauss

Question 39

Which material has the property of allowing electric current to flow through it easily?

Accepted Answer

Metal

Answer

Plastic

Answer

Wood

Answer

Rubber

Question 40

What is the fundamental principle behind the operation of an electric generator?

Accepted Answer

The conversion of mechanical energy into electrical energy through electromagnetic induction

Answer

The flow of electrons in a circuit

Answer

The generation of electromagnetic waves

Question 41

Which factor does NOT influence the strength of an electromagnetic field?

Accepted Answer

Temperature of the medium

Answer

Number of turns in a coil

Answer

Strength of the current

Question 42

Which of the following statements is NOT true about electromagnetic waves?

Accepted Answer

They need a medium to travel through.

Answer

They are transverse waves.

Answer

They travel at the speed of light in a vacuum.

Answer

They can exhibit wave-particle duality.

Question 43

What is the approximate frequency range of visible light?

Accepted Answer

400 to 790 THz

Answer

3 Hz to 30 Hz

Answer

300 GHz to 3 THz

Answer

10 MHz to 100 MHz

Question 44

Which of these technologies directly demonstrates the wave-particle duality of electromagnetic waves?

Accepted Answer

Electron microscopy

Answer

Optical fiber communication

Answer

Radio broadcasting

Answer

X-ray imaging

Question 45

What is the speed of light in a vacuum?

Accepted Answer

299,792,458 meters per second

Answer

186,000 miles per second

Answer

340 m/s

Answer

The speed of sound

Question 46

Which device converts electromagnetic waves into sound waves?

Accepted Answer

Radio receiver

Answer

Laser pointer

Answer

Light bulb

Answer

Solar cell

Question 47

An electromagnetic wave vibrating only in the vertical plane is said to have which type of polarization?

Accepted Answer

Vertical

Answer

Horizontal

Answer

Elliptical

Answer

Circular

Question 48

Which of the following is NOT an electromagnetic wave?

Accepted Answer

Sound wave

Answer

Microwaves

Answer

Light wave

Answer

X-ray

Question 49

What is the standard unit for measuring the intensity of electromagnetic radiation?

Accepted Answer

Watts per square meter (W/m²)

Answer

Newtons per square meter (N/m²)

Answer

Candela per square meter (cd/m²)

Question 50

Which of the following electromagnetic waves has the highest energy?

Accepted Answer

Gamma waves

Answer

Microwaves

Answer

Ultraviolet waves

Question 51

What is the wavelength of a radio wave with a frequency of 1 MHz?

Accepted Answer

300 meters

Answer

3 kilometers

Answer

3000 meters

Answer

30 meters

Question 52

Which of the following devices utilizes electromagnetic waves?

Accepted Answer

Mobile phone

Answer

Pendulum

Answer

Ruler

Answer

Spring

Question 53

In a vacuum, what is the speed of electromagnetic waves?

Accepted Answer

3 x 10^8 m/s

Answer

7 x 10^8 m/s

Answer

1 x 10^8 m/s

Answer

5 x 10^8 m/s

Question 54

Which material on the list is transparent to electromagnetic waves?

Accepted Answer

Glass

Answer

Rubber

Answer

Metal

Answer

Wood

Question 55

What is the unit of measurement for electric field strength?

Accepted Answer

Newtons per coulomb (N/C)

Answer

Volts per meter (V/m)

Answer

Watts per square meter (W/m^2)

Answer

Tesla (T)

Question 56

What is the relationship between the electric field strength and the magnetic field strength of an electromagnetic wave?

Accepted Answer

They are perpendicular to each other and have a proportional relationship.

Answer

They are perpendicular to each other and have an inverse relationship.

Answer

They are parallel to each other and have an inverse relationship.

Question 57

Which of the following is not a type of electromagnetic wave?

Accepted Answer

Sound wave

Answer

Radio wave

Answer

X-ray

Answer

Light wave

Question 58

What is the wavelength of an electromagnetic wave with a frequency of 500 THz?

Accepted Answer

6 x 10^-4 meters

Answer

6 x 10^-8 meters

Answer

6 x 10^-6 meters