OAR OAR Mechanical Comprehension: Electricity 2

Question 1

Two resistors of 6Ω and 12Ω are connected in parallel. What is the equivalent resistance?

Accepted Answer

4Ω

Answer

For parallel resistors, 1/R = 1/6 + 1/12 = 3/12, so R = 4Ω.

Question 2

A 100W light bulb operates on a 120V circuit. What current does it draw?

Accepted Answer

0.83A

Answer

Using P = IV, I = P/V = 100/120 ≈ 0.83A.

Question 3

What happens to the total resistance when additional resistors are added in series?

Accepted Answer

It increases

Answer

In a series circuit, total resistance is the sum of all individual resistances, so it always increases as more resistors are added.

Question 4

Which material is the best electrical conductor?

Accepted Answer

Silver

Answer

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

Question 5

A circuit has a 9V battery and a single 3Ω resistor. What power is dissipated?

Accepted Answer

27W

Answer

Using P = V²/R = 81/3 = 27W.

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