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resistance.
S1-Q12.) Voltage in an electrical system is calculated by the formula:

a.) E = P/I
P=I*E so solving for E =P/I.
b.) E = I*R
Ohm’s Law Voltage is directly proportional to the size of the restriction (resistance) and the flow
trying to get through that resistance.
c.) E = √(P*R)
E= P/I, but when I is not known, you can substitute E/R (I=E/R) into the equation since it equals I
E= (P/(E/R)), then simplifying, E=PR/E. Cross multiplying, E2 = PR or E = √(P*R) .
d.) *All of the above
Correct. All three may be used to solve for E.

S1-Q13.) What is the unit of measure for electrical pressure or electromotive force?

a.) Amps
Amps indicates the amount of flow. Flow is determined by the number of electrons passing a certain
point over a period of time. 6 x 1018 electrons passing a point in 1 second equals 1 amp.
b.) Ohms
Ohms is the resistive value of the material the current is flowing through. Increase resistance will
cause increased voltage if current remains the same.
c.) *Volts
Correct. Volts are the potential, the force (electromotive force) behind the current. Without a
difference in potential, there would be no flow.
d.) Watts
Watts are the unit of power. Volts times amps equals watts.

S1-Q14.) A parallel circuit configuration exhibits which of the following characteristics?

a.) Each component drops a different amount of voltage depending on its resistance
One of the primary attributes are that all branches in a parallel circuit use the same amount of voltage
like the way a car is wired. Each device uses 12 volts.
b.) *Each component has a different amount of current running through it unless all the
resistive values are identical
Correct. Depending on the load size the currents will differ. Smaller resistance will carry more
current (path of least resistance), larger resistance will carry less current.
c.) The total resistance will always be larger than the largest individual resistance.
This is opposite of the truth. The total resistance will always be less than the smallest resistance.
d.) All of the above

EGSA Apprentice Certification Program Study Guide - Page 60