Ch 30: Electromagnetic WavesSee all chapters
All Chapters
Ch 01: Units & Vectors
Ch 02: 1D Motion (Kinematics)
Ch 03: 2D Motion (Projectile Motion)
Ch 04: Intro to Forces (Dynamics)
Ch 05: Friction, Inclines, Systems
Ch 06: Centripetal Forces & Gravitation
Ch 07: Work & Energy
Ch 08: Conservation of Energy
Ch 09: Momentum & Impulse
Ch 10: Rotational Kinematics
Ch 11: Rotational Inertia & Energy
Ch 12: Torque & Rotational Dynamics
Ch 13: Rotational Equilibrium
Ch 14: Angular Momentum
Ch 15: Periodic Motion (Oscillations)
Ch 16: Waves & Sound
Ch 17: Fluid Mechanics
Ch 18: Heat and Temperature
Ch 19: Kinetic Theory of Ideal Gasses
Ch 20: The First Law of Thermodynamics
Ch 21: The Second Law of Thermodynamics
Ch 22: Electric Force & Field; Gauss' Law
Ch 23: Electric Potential
Ch 24: Capacitors & Dielectrics
Ch 25: Resistors & DC Circuits
Ch 26: Magnetic Fields and Forces
Ch 27: Sources of Magnetic Field
Ch 28: Induction and Inductance
Ch 29: Alternating Current
Ch 30: Electromagnetic Waves
Ch 31: Geometric Optics
Ch 32: Wave Optics
Ch 34: Special Relativity
Ch 35: Particle-Wave Duality
Ch 36: Atomic Structure
Ch 37: Nuclear Physics
Ch 38: Quantum Mechanics

Concept #1: What is an Electromagnetic Wave?

Practice: If a lightyear is defined as the distance light travels in one year, what do you think a lightminute is? If Mars is 12 lightminutes away, how far away is it in meters? How long would it take to send a radio transmission to Mars?

Additional Problems
The energy that light carries is related to the frequency of the light by the equation E = hf where h is a constant equal to 6.626x10 -34 Js. Blue light of wavelength 400 nm passes from air into a medium with an index of refraction of 1.7.  (a) What is the energy of the light in air? (b) What is the energy of the light in the medium?
A 7.55 x 1014 Hz electromagnetic wave propagates in carbon tetrachloride with a speed of 2.05 x 108 m/s. The wavelength of the wave in carbon tetrachloride is closest to: A) 338 nm B) 272 nm C) 361 nm D) 301 nm E) 397 nm
What is the essential difference between microwaves and blue light? a) There is no essential difference in the nature of microwaves and blue light other than a difference in frequency and wavelength. b) Blue light is a beam of photons. Microwaves are not photons. c) One has an electric charge, the other does not.  d) One is a form of radiation, the other is not. e) One undergoes refraction, the other does not. 
Light travels through a medium with a permittivity of 1.7ε 0 and a permeability of 2μ0. What is the speed of light in this medium?
When light travels from air to water,A) its velocity, wavelength and frequency all change.B) its velocity and wavelength change, but its frequency does not change.C) its velocity changes, but its frequency and wavelength do not change.D) its wavelength changes, but its velocity and frequency do not change.E) It's frequency changes, but its velocity and wavelength do not change.
Two electromagnetic waves are traveling at the same speed. The wave with the higher wavelengthA) is traveling faster than the other wave.B) has a higher frequency than the other wave.C) is traveling slower than the other wave.D) has a lower frequency than the other wave.
A 1.83 x 1014 Hz electromagnetic wave propagates in carbon tetrachloride with a speed of 2.05 x 108 m/s. The wavelength of the wave in air is closest to:A) 1390 nmB) 1490 nmC) 1240 nmD) 1640 nmE) 1120 nm
Light having a frequency in vacuum of 6.0 x 10 14 Hz enters a liquid of refractice index 2.0. In this liquid, its frequency will be a) 1.5 x 1014 Hzb) 6.0 x 1014 Hzc) 3.0 x 1014 Hzd) 12 x 1014 Hz e) None of the above choices are correct.
Which one of the following type of electromagnetic wave travels through space and fastest?A) radio wavesB) infraredC) ultravioletD) microwavesE) They all travel through space at the same speed.
A radio station broadcast at 80 MHz. How long does it take for this radio signal to travel a distance of 2.0 x 107 m through space? (c = 3.0 x 108 m/s)A) 0.15 x 10-2 sB) 15 msC) 6.7 x 10-2 sD) 20 msE) 25 ms
The sun is 1.5 × 10 8 km from Earth. The index of refraction for water is 1.263.  How much longer would it take light from the sun to reach Earth if the space between them were filled with water rather than a vacuum?
The plot below depicts the electric field component of a linearly polarized, electromagnetic plane wave traveling through vacuum. E(r,t) propagates in the negative  z-direction and toward an observer located at z = 0. (Note that x is directed into the page.) If the observer begins moving in the positive z-direction, the speed of propagation of the wave willa) increase.b) decrease.c) stay the same.
Microwaves of frequency 6.0 GHz travel through a particular material of length 26.0 m at a speed 15% slower than the speed of light in vacuum. Approximately how many complete wavelengths fit inside the material? (1) 610 (2) 520 (3) 2560 (4) 3250 (5) 3470
Two bursts of light of the same wavelength are emitted simultaneously in parallel beams. Beam 1 passes through 1.6 m of material with index of refraction 1.8 while beam 2 passes through a material of index of refraction 2.3. What is the length of the second material so that both beams emerge from their respective materials at the same time? (1) 1.25 m (2) 2.04 m (3) 1.60 m (4) 2.59 m (5) 1.30 m
What is the frequency for green light? (λ = 550 nm)A. 5.45 x 1011 HzB. 165 HzC. 1.65 x 1014 HzD. 5.45 x 1014 HzE. 1.65 x 1017 Hz
Which of the following is true about an electromagnetic wave propagating in a vacuum? A. The electric and magnetic fields are PARALLEL and |B|=c|E| B. The electric and magnetic fields are PERPENDICULAR to each other and |E|=c|B| C. The electric and magnetic fields are PERPENDICULAR to the propagation direction D. A & B E. B & C
Two electromagnetic waves are travelling at the same speed. The wave with the higher wavelengthA) has a lower frequency than the other wave.B) has a higher frequency than the other wave.C)  is traveling slower than the other wave.D) is traveling faster than the other wave.