Chapter 5 - Electrical Circuits and OHM's Law

If an insulated wire rubbed through a part of the insulation and the wire conductor touched the steel body of a vehicle, the type of failure would be called a(n) ________.

Short-to-ground

If two insulated wires were to melt together where the copper conductors touched each other, the type of failure would be called a(n) ________.

Short-to-voltage

If 12 volts are being applied to a resistance of 3 OHMs, _________ amperes will flow.

[Amps = Volts / OHMs] 12 / 3 = 4

How many watts are consumed by a light bulb if 1.2 amperes are measured when 12 volts are applied?

[Watt = Amps x Volts] 1.2 amps x 12 volts = 14.4 watts

How many watts are consumed by a starter motor if it draws 150 amps at 10 volts?

150 amps x 10 volts = 1,500 watts [Watt = Amps x Volts]

High resistance in an electrical circuit can cause ____________.

Dim lights, slow motor operation, and clicking of relays or solenoids.

If the voltage increases in a circuit, what happens to the current (amperes) if the resistance remains the same?

It increases.

If 200 amps flow from the positive terminal of a battery and operate the started motor, how many amperes will flow back to the negative terminal of the battery?

200 amperes.

What is the symbol for voltage used in calculations?

E

What is the symbol used for watts in calculations?

P

What is the symbol used for amps in calculations?

I

Which circuit failure is most likely to cause the fuse to blow?

Short-to-ground

OHM’s law states

It requires 1 volt to push 1 amp through 1 ohm of resistance.