Circuit breakers and fuses are rated for voltage, current, and which of the following? -
answer Time delay
The standard notation for switch contacts include which of the following? - answer
Number of poles, number of fixed contacts per pole
The characteristic of a resistor that indicates the acceptable deviation of value from the
indicated value is called which of the following? - answer Tolerance
What are the acceptable limits of deviation of resistance for a 4.2 k resistor rated at 5%?
- answer 3.99 k and 4.41 k
The bands from left to right on a resistor indicate the numbers 5, 4, and 3. What is its
value? - answer 54,000 ohms
A resistor of what power rating including safety factor would be needed to replace a
resistor in a circuit operating with a 125v voltage drop and 500mA of current? - answer
125 W
What distinguishes a rheostat from a potentiometer? - answer A rheostat is a two-
terminal device
What can add an extra layer of safety when using power tools? - answer Ground
fault circuit interrupter
If a partially-shorted circuit that has a 5 amp fuse and
normally carries 2 amps, causes the current to double
what would happen to the fuse? - answer The fuse would hold the load
A brake coil has a normal resistance of 50 ohms and
operates at 120 volts. What is its current? - answer 2.4 amps
Three parallel branches of a circuit measure 4, 4, and 2 amps. What is the total current?
- answer 10 amps
A circuit with parallel branches has 3000 ohms in one branch and 3000 ohms in the
other. What is the total resistance? - answer 1500 ohms
What is the circuit current for a circuit containing two 2500 ohm series relay coils with
125 volts applied? - answer .025 amps