Question

question: which device uses an armature and two contact screws in one circuit and an electromagnet in a separate circuit? answer options: select one of four electric relay telephone receiver step-up transformer dc generator

Explanation:

An electric relay has an electromagnet in one circuit (the control circuit) and an armature with contact screws in another circuit (the load circuit) to control the load circuit using the electromagnet's magnetic field. A telephone receiver converts electrical signals to sound, a step - up transformer changes voltage levels using electromagnetic induction (no armature with contact screws as described), and a DC generator converts mechanical energy to electrical energy (different structure).

Answer:

A. Electric relay