OAR OAR Mechanical Comprehension: Electricity Questions and Answers 2

Question 1

A circuit contains a 12V battery and a 4-ohm resistor. What is the current flowing through the circuit?

Accepted Answer

3 A

Answer

Using Ohm's law (I = V/R), 12V divided by 4 ohms equals 3 amperes.

Question 2

What happens to the total resistance when resistors are connected in parallel?

Accepted Answer

It decreases below the smallest individual resistor

Answer

In a parallel circuit, the total resistance is always less than the smallest individual resistor value.

Question 3

Which material is the best electrical conductor?

Accepted Answer

Silver

Answer

Silver has the highest electrical conductivity of all elements, making it the best conductor.

Question 4

In a series circuit with three identical light bulbs, what happens if one bulb burns out?

Accepted Answer

All bulbs go out

Answer

In a series circuit there is only one path for current, so a break anywhere stops all current flow.

Question 5

What is the unit of electrical power?

Accepted Answer

Watt

Answer

The watt is the SI unit of power, defined as one joule per second or one volt times one ampere.

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