Question

9
olivia is working on a science activity. she takes an iron rod and wraps insulated copper wire around it. she connects the ends of the copper wire to the battery. olivia switches on the circuit and brings some paper clips near the iron rod. the paper clips are attracted to the iron rod. (ps2 - 3/ps2.b)
which of the following will cause the paper clips to fall off the iron rod? *
(1 point)
○ increase the current flow through the circuit
○ switch on the circuit to start the current flow
○ increase the copper wiring around the iron rod
○ switch off the circuit to stop the electric current

Explanation:

The setup is an electromagnet (iron rod with copper wire coil, connected to a battery). An electromagnet's magnetism depends on electric current. When the circuit is switched off, current stops, so the iron rod loses magnetism, and paper clips (attracted by magnetism) fall off. Let's analyze options:

• "increase the current flow through the circuit": Increases magnetism, paper clips stay or are more attracted. Eliminate.
• "switch on the circuit to start the current flow": Starts magnetism, paper clips get attracted (opposite of falling off). Eliminate.
• "increase the copper wiring around the iron rod": More coils increase magnetism, paper clips stay. Eliminate.
• "switch off the circuit to stop the electric current": Stops current, electromagnet loses magnetism, paper clips fall. Correct.

Answer:

D. switch off the circuit to stop the electric current (Note: Assuming the options are labeled as A, B, C, D with D being "switch off the circuit to stop the electric current" based on the order: 1st option A, 2nd B, 3rd C, 4th D)