Amazon Maintenance Technician: Math Ohm's Law 2

Question 1

Using Ohm's Law, if voltage is 120V and resistance is 40Ω, what is the current?

Accepted Answer

3A

Answer

I = V ÷ R = 120 ÷ 40 = 3 amperes.

Question 2

A circuit has a current of 5A and resistance of 24Ω. What is the voltage?

Accepted Answer

120V

Answer

V = I × R = 5 × 24 = 120 volts.

Question 3

The voltage across a resistor is 60V and the current through it is 2A. What is the resistance?

Accepted Answer

30Ω

Answer

R = V ÷ I = 60 ÷ 2 = 30 ohms.

Question 4

Three resistors of 10Ω, 20Ω, and 30Ω are connected in series. What is the total resistance?

Accepted Answer

60Ω

Answer

Series resistance: R_total = R1 + R2 + R3 = 10 + 20 + 30 = 60Ω.

Question 5

A motor draws 15A from a 240V supply. What is the power consumed?

Accepted Answer

3,600W

Answer

P = V × I = 240 × 15 = 3,600 watts.

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