SEW Day 2

Question 1

static electricity

Answer 1

• The separation of charges
• Opposite charges attract and like charges repel each other

Question 2

Current Electricity

Answer 2

The movement of electrons through a conductive material in a uniform direction

Question 3

Magnetism

Answer 3

• force exerted by magnet when they attract or repel each other.
• Caused by the motion of electric charges

Question 4

Charles-Augustin de Coulomb

Answer 4

• 18th century
• attractive and repulsive nature of electrical charges and magnets
• inverse square law, the force is inversely proportional to the square of the distance between the charges

Question 5

André-Marie Ampère

Answer 5

• 19th century physicist
• relationship b/w electricity and magnetism
• magnetic needle affected by current in a wire

Question 6

Michael Faraday

Answer 6

• 1821
• link b/w electricity and magnetism
• magnet and electricity in wire
• light can be affected by electrical currents

Question 7

James Clerk Maxwell

Answer 7

• 1862
• speed of electromagnetic field = speed of light
• light is an electromagnetic disturbance

Question 8

Electromagnetic (EM) Radiation

Answer 8

the flow of energy (photons) at the speed of light through free space or through a material medium in the form of electric and magnetic fields that make up electromagnetic waves

Question 9

photon

Answer 9

The movement produces an oscillating (orthogonal) e-field and b-field, which travel perpendicular to each other in a bundle energy

Question 10

Young’s Double Slit Experiment:

Answer 10

Proved Light exhibits properties of waves

Question 11

Electromagnetic Wave

Answer 11

a wave that is composed of oscillating magnetic and electric fields.

Question 13

sine wave

Answer 13

continuous, uniform wave with a constant frequency, amplitude, and phase.

Question 14

Characteristics of a Wave

Answer 14

Amplitude
Wavelength
Frequency
Phase
Polarization

Question 15

Amplitude

Answer 15

• A
• height of wave
  power

Question 17

wavelength

Answer 17

• λ
• distance from peak to peak, trough to trough

Question 18

Frequency

Answer 18

• v
• number of cycles per second
• hertz
• 1000hz = 1KHz…what is 1 GHz? 1,000,000,000 Hz = 1M KHz = 1000 MHz = 1 GHz

Question 19

1000hz = 1KHz…what is 1 GHz?

Answer 19

1,000,000,000 Hz = 1M KHz = 1000 MHz = 1 GHz

Question 20

Wavelength and Frequency Relationship

Answer 20

the shorter the wavelength, greater the frequency (inversely proportional)

Question 21

Energy and Frequency Relationship:

Answer 21

The greater the frequency the higher the energy (directly proportional)

Question 22

Phase

Answer 22

• ⏀
• offset

Question 23

Polarization

Answer 23

• orientation of a wave, typically from the e-field perspective
• linear or circular

Question 24

Atmospheric layers

Answer 24

o Low frequency – effected by scintillation
o High frequency – effected by atmospheric effects (water droplets and moisture
o Middle – X band (IEEE), best place/balance

Question 25

Atmospheric Windows

Answer 25

regions in the EM spectrum where energy can be fully transmitted

Question 26

Atmospheric Absorption

Answer 26

caused by Water Vapor (H20) Carbon Dioxide (CO2) Ozone (O3)

Question 27

Atmosphere Scattering

Answer 27

Absorption + Scattering = Attenuation

Question 28

Atmospheric Refraction

Answer 28

high pressure + low temperature = larger refraction angle

Question 29

Scintillation

Answer 29

Scintivariations in strength, position, and polarization of a transmitted signals passing through a mediumllation