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1-48. In a comparison of waves of light and
sound as they travel from an air into
water, how is the speed of (a) light waves
and (b) sound waves affected?
1. (a) Increased
(b) increased
2. (a) Increased
(b) decreased
3. (a) Decreased
(b) decreased
4. (a) Decreased
(b) increased
1-49. Which of the following waves are NOT a
form of electromagnetic energy?
1. Heat waves
2. Sound waves
3. Light waves
4. Radio waves
1-50. The electromagnetic spectrum represents
the entire range of electromagnetic waves
arranged in the order of their
1. color
2. frequency
3. visibility
4. application
1-51. Which of the following portions of the
frequency spectrum contains the highest
frequency?
1. X-ray
2. Radar
3. Light
4. Cosmic
1-52. Which of the following electronic
devices is used to radiate and/or collect
electromagnetic waves?
1. Antenna
2. Receiver
3. Transmitter
4. Transmission line
1-53. The electric field and magnetic field
combine to form which of the following
types of waves?
1. Spherical
2. Elliptical
3. Electromagnetic
4. Each of the above
1-54. The magnetic field radiated from an
antenna is produced by what electrical
property?
1. Voltage
2. Current
3. Reactance
4. Resistance
1-55. The electric field radiated from an
antenna is produced by what electrical
property?
1. Voltage
2. Current
3. Reactance
4. Resistance
1-56. Applying rf energy to the elements of an
antenna results in what phase relationship
between voltage and current?
1. Voltage lags current by 90 degrees
2. Voltage leads current by 90 degrees
3. Voltage and current are 180 degrees
out of phase
4. Voltage and current are in phase
1-57. What field exists close to the conductor
of an antenna and carries the current?
1. Electric
2. Magnetic
3. Induction
4. Radiation
