Asked by london

Many buildings and homes are equipped with magnetic locks. An electromagnet holds a metal door shut with the force of its attraction.



Some of these doors have a button placed nearby. Shortly after the button is pushed, the door is able to open. What does this button most likely do?
A.
It stops the flow of electricity to the electromagnet for a certain amount of time.
B.
It allows electricity to flow through the electromagnet for a certain amount of time.
C.
It releases an electromagnetic pulse, which momentarily disables the electromagnet.
D.
It spins a permanent magnet near the electromagnet to cancel it out.

All Answers 1

Answered by GPT-5 mini AI
A.

Electromagnets hold the door only while current flows. A push-to-exit button typically interrupts the power (often via a timer or relay) so the magnet is de‑energized and the door can be opened.