Unit 2-4 Lesson 1
When a coil induces a voltage into itself, it is known as ? inductance. a. auto b. back c. counter d. self
D
If an iron core is inserted into a coil, the inductance of the coil will decrease. Select one: True False
False
If the current flowing through a conductor decreases, the magnetic field around the conductor will increase. Select one: True False
False
Moving a magnetic field across a stationary conductor will not induce a voltage in the conductor. Select one: True False
False
Cutting more magnetic lines of force per second will increase the amount of voltage induced into a conductor. Select one: True False
True
For a voltage to be induced in a conductor, there must be relative motion between the conductor and a magnetic field. Select one: True False
True
Inductance has no effect on a DC circuit as long as the current is constant. Select one: True False
True
Lenz's Law states, "An induced voltage or current opposes the motion that created the induced voltage or current." Select one: True False
True
The inductance of a coil is directly related to the number of turns of wire that make up the coil. Select one: True False
True
A coil of wire wrapped around a core is called a(n) ? . a. capacitor b. inductor c. magneto d. transducer
B
Maximum EMF is induced when a conductor cuts a magnetic field at ? . a. 0° b. 90° and 270° c. 180° d. 360°
B
The ability of a current-carrying conductor, coil, or circuit to induce a voltage into itself or adjacent circuits is called ? . a. coupling b. inductance c. reactance d. transference
B
The flux lines that do not link to all the other coils do not contribute to the total inductance, and are called ? flux. a. disconnected b. leakage c. scattered d. wasted
B
The letter ? is used in calculations to represent inductance. a. I b. L c. M d. N
B
The ability of a moving or changing magnetic field to induce a voltage into a conductor is called ? . a. conduction b. coupling c. inductance d. reaction
C
A transformer operates under the principle of ? . a. coil interaction b. electrical coupling c. magnetic transfer d. mutual induction
D
The ability of a material to focus, or concentrate, magnetic lines of force is called magnetic ? . a. absorption b. amplification c. constriction d. permeability
D
Another term for counter EMF is ? EMF. a. back b. opposing c. residual d. reverse
A
Whenever ? flows through a conductor, a magnetic field is created. a. current b. electromotive force c. inductance d. voltage
A
The ability of one coil to induce a voltage into another coil is called ? induction. a. common b. magnetic c. mutual d. shared
C
The induced voltage is ? out of phase with the applied voltage. a. 0° b. 90° c. 180° d. 360°
C
The unit of inductance is called the ? . a. farad b. gilbert c. henry d. mho
C
When a conductor that is cutting through a magnetic field changes direction, the ? of the induced voltage will be reversed. a. frequency b. intensity c. polarity d. velocity
C
When there is no current flowing through a conductor, the magnetic field around the conductor is ? . a. decreasing b. increasing c. not present d. reversing
C