25 4-10.   Moving electric and magnetic fields in space have what (a) phase and (b) angular relationships? 1.  (a) In phase (b) Perpendicular 2.  (a) In phase (b) Displaced 45º 3.  (a) Out of phase (b) Displaced 45º 4.  (a) Out of phase (b) Perpendicular 4-11.   What is the length of each half of the wire for a dipole antenna? 1.  Wavelength 2.  3/4 wavelength 3.  1/2 wavelength 4.  1/4 wavelength 4-12.   On a dipole antenna, the sinusoidal variation in charge magnitude lags the sinusoidal variation in current by what amount? 1.  1    cycle 2.  1/2 cycle 3.  1/4 cycle 4.  1/8 cycle 4-13.   On a standing wave, the points of high current and voltage are identified by which of the following terms? 1.  Peaks 2.  Nodes 3.  Poles 4.  Loops 4-14.   The presence of standing waves indicates which of the following conditions of an antenna? 1.  Resonance 2.  Saturation 3.  Nonresonance 4.  Minimum efficiency 4-15.   The antenna property that allows the same antenna to both transmit and receive energy is 1.  gain 2.  resonance 3.  reciprocity 4.  directivity 4-16.   There is a ratio between the amount of energy propagated in certain directions by a directional antenna compared to the energy that would be propagated in these directions if the antenna were not directional. This ratio is known as which of the following antenna characteristics? 1.  Gain 2.  Directivity 3.  Reciprocity 4.  Polarization 4-17.   The polarization plane of the radiation field is determined by which of the following fields? 1.  Electric field only 2.  Magnetic field only 3.  Electromagnetic field 4-18.   For best reception of a signal from a horizontally polarized antenna, the receiving antenna should be mounted so that it has what relationship with the transmitting antenna? 1.      0 degrees 2.    45 degrees 3.    90 degrees 4.  135 degrees 4-19.   An electric field that rotates as it travels through space exhibits what type of polarization? 1.  Vertical 2.  Spherical 3.  Elliptical 4.  Horizontal