BMST Electrical Circuits and Ohm's Law 4

Question 1

A 60 W light bulb operates at 120 V. What is its resistance?

Accepted Answer

240 Ω

Answer

Using P = V²/R, R = V²/P = 14400/60 = 240 Ω.

Question 2

In a series circuit, which quantity remains the same throughout?

Accepted Answer

Current

Answer

In a series circuit, the same current flows through every component since there is only one path.

Question 3

What is the voltage drop across a 15 Ω resistor when 3 A flows through it?

Accepted Answer

45 V

Answer

V = IR = 3 × 15 = 45 V.

Question 4

Which material is the best conductor of electricity?

Accepted Answer

Copper

Answer

Copper is an excellent conductor with very low electrical resistance, making it widely used in wiring.

Question 5

A circuit has a 12 V source and three equal resistors in series drawing 0.5 A. What is each resistor's value?

Accepted Answer

8 Ω

Answer

Total R = V/I = 12/0.5 = 24 Ω; each of three equal resistors = 24/3 = 8 Ω.

BMST - Basic Math and Science Test Practice Test