Bennett Mechanical Test Electricity and Circuits 4

Question 1

What instrument measures electrical current?

Accepted Answer

Ammeter

Answer

An ammeter measures current and is connected in series with the circuit.

Question 2

If voltage stays constant and resistance increases, what happens to current?

Accepted Answer

Current decreases

Answer

By Ohm's law, current is inversely proportional to resistance at fixed voltage.

Question 3

What is created around a wire when current flows through it?

Accepted Answer

A magnetic field

Answer

Current flowing through a conductor produces a magnetic field around it.

Question 4

Three 4-ohm resistors are connected in series. What is the total resistance?

Accepted Answer

12 ohms

Answer

Series resistances add, so 4 + 4 + 4 = 12 ohms.

Question 5

Why are appliances in a home wired in parallel rather than series?

Accepted Answer

So each can operate independently at full voltage

Answer

Parallel wiring lets each appliance get full voltage and work independently.

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