Chpt 4

Question 1

Who first discovered photons?

Answer 1

Ancient Greeks

Question 2

A photon is also known as what?

Answer 2

Electromagnetic energy

Question 3

Two examples of electromagnetic energy

Answer 3

light
x-rays

Question 4

What is the smallest quantity of any electromagnetic radiation?

Answer 4

photon

Question 5

What is pictured as a small bundle of energy or Quantum that travels through space at the speed of light?

Answer 5

photon

Question 6

(T/F) An X-ray photon is a quantum of electromagnetic energy

Answer 6

True

Question 7

Do EM waves require a medium to travel?

Answer 7

No, they can travel in a vacuum

Question 8

What other form can EM waves travel in?

Answer 8

As a sine wave

Question 9

Four characteristics of a sine wave

Answer 9

Speed, wavelength, frequency, amplitude

Question 10

What is the top of the wave called? The bottom?

Answer 10

Crest, Trough

Question 11

What is the speed of light?

Answer 11

3 x 10^8 m/s

Question 12

What is the distance between two successive points on a wave?

Answer 12

wavelength

Question 13

A wavelength is measured in? (2)

Answer 13

Angstroms or meters

Question 14

One angstrom is how many meters?

Answer 14

1 A = 10^-10

Question 15

What is the intensity of the wave defined by its maximal height or is one-half the range from the crest to the valley?

Answer 15

Amplitude

Question 16

What is the number of cycles per second?

Answer 16

Frequency

Question 17

What is frequency measured in?

Answer 17

cycles/sec or Hertz (Hz)

Question 18

1 Hz is how many cycles per second

Answer 18

1 Hz = 1 cycle/sec

Question 19

Wavelength and frequency have what relationship and why?

Answer 19

Inversely proportional, because in the equation c is constant

Question 20

EM energy is measured in what?

Answer 20

Electron volts (eV)

Question 21

The energy of 1 electron passing through a potential difference of 1 volt is what?

Answer 21

1 eV

Question 22

1 eV = ? joules?

Answer 22

1.6 x 10^-19 joules

Question 23

EM radiation needs what eV to have the ability to ionize

Answer 23

10 eV or higher

Question 24

When an atom gains or loses an electron

Answer 24

Ionization

Question 25

Types of ionizing radiation (3)

Answer 25

UV, X-rays, Gamma rays

Question 26

What is wave-particle duality?

Answer 26

When it acts like a particle but is a wave and vice-versa

Question 27

Bundles of EM energy act like what when they interact with matter?

Answer 27

particles

Question 28

The energy of the photon is ____ proportional to the frequency of the wave.

Answer 28

directly