Electronic Information Practice Set 1 and 2
A fixed resistor has a color band pattern of black orange, orange. What is it's resistance?
3000 ohms
A European traveler brings his hair dryer to the United States. The specifications on the small appliance say it draws 10 amps when on a standard household circuit, which is 220 volts in Europe. What will it draw if connected directly to a U.S. power source of 110 volts? 220 Divide 10 = 22 ohms 110 divide 22 = 5amps
5 amps
Two identical resistors are wired in parallel in a circuit. The voltage drop across these resistors is 18 volts, and the total current in the circuit is 6 amps. What is the resistance of either resistor? (18 Subtracted 6 divided 2)
6 Ω
A 2.5 V battery is used to power a cordless phone. An ammeter shows the current flow is 30 A through the phone when it is on. How power does the phone use? Multiply (x)
75w
A shop vac is plugged into a 120 V generator. Given a total current flow of 15 A, what must the total resistance of the vacuum cleaner be? (Divided)
8 Ω
A simple circuit with a 10-volt battery and a 4-ohm resistor has a current of 2.5 amps running through it. When a second resistor is added, the amperage drops to 2 amps. What was the other resistor, and how was it wired to the circuit?
A 1-ohm resistor, wired in series
When a P-type material is joined with an N-type material, what is created?
a diode
Which of the following would not increase the rate of direct current flow, I, through a conductor?
adding an inductor to the circuit (in series)
A circuit with flowing current in it can be assumed to be
closed
Given a circuit with a single resistor, add two more resistors to the circuit, both with the same resistance value as the original resistor, one in parallel with the original resistor, and one in series with them both, will cause the overall resistance to
definitely increase
Current can be expressed in
milliamperes
Why is copper favored over other conducting materials like aluminum and silver?
Copper has low resistance relative to its cost
Which switch, if flipped, would not close the in the diagram shown?
S4
How much current will flow in a circuit that has 60 mV applied to a 15 ΚΩ resistance?
0.004 mA
What is the current in the 20-ohm resistor?
1 amp
A V battery is used to provide power to a flashlight whose 10 W light bulb is the only load in the circuit. What is the amount of current flow through the flashlight?
1.67 A
What voltage is required for 30 A to flow through a 60 ΚΩ resistance ?
1.8 MV
A circuit includes three 2 Ω resistors wired in parallel What is their effective resistance?
2 over 3 Ω
Which is the collector in the transistor symbol below?
2
Given a lamp wired in a simple AC household circuit, which of the following will cause the light to dim the most?
An inductor wired in series with the lamp
In the circuit diagram pictured, where the two lamps have identical loads, what will be the effect of closing the switch?
L1 will light up and L2 will remain at the same brightness the power draw on the battery will double.
Plugs are often differently shaped in different countries to prevent foreign electronics from drawing on an electric grid they weren't designed for. What would happen if a device designed for a 150-volt source were forced into a plug providing 240 volts?
The device might burn out due to higher current.
Which of the following is one of the reasons neighborhood are connected to the power grid via electrical substations instead of being wired into long distance powerline directly?
The substation transforms the efficients high-voltage power coming off the lines to a safer, lower value for household use.
Given the following DC circuit, which has been open for some time, what will happen after the switch is closed?
The total current flow will be smaller when the lamp first lights, then increase dramatically
How does direct current (DC) flow in a conductor?
one way
Given the image below, which shell is the valence shell in a copper atom?
the fourth
A simple parallel circuit with resistances of 2.5 Ω and 5.0 Ω respectively will have
twice as much current in the 2.5 Ω resistor
