Question
QUESTION 24 1 po A solenoid consists of O a burglar alarm relay O two plates separated by an insulator O a permanent magnet O a coil of wire wound around a core QUESTION 25 1 p The movable part of the relay is the: O the armature. O electromagnetic coil. O magnetic field. O all of these. Question Completion Status: QUESTION 26 Increasing the speed at which a magnet moves through a coil of wire causes the induced voltage to O decrease O remain the same O increase QUESTION 27 Electromagnetic induction is best defined as the process by which a voltage is produced in a conductor when there is: O energy produced by the rotating coils. O motion around the magnetic felds. O motion between the magnetic poles. O motion between the conductor and the magnetic field. QUESTION 28 A strong magnetic field around a conductor indicates a small current flowing through the conductor. O True O False QUESTION 29 If a relay picks up and makes a contact but does not stay picked up, what's the trouble? O The magnetic field is too strong. O The relay coil is open. O The magnetic field is too weak. O There is no trouble. The relay is operating normally. QUESTION 30 An ampere-turn is a unit of O magnetomotive force (mmf) O resistance O reactance QUESTION 31 Aluminum, brass, and iron make good magnets. O True O False QUESTION 32
Explanation / Answer
Question 24
Ans: A coil of wire wound around a core.
Solenoid is a coil usually wound around a metallic core to produce a uniform magnetic field. It's usually used as a electromagnet to produce control magnetic field when current is passed through it
