Interview Question in circuits |
|
|
|
digital circuit, digital circuit design, digital integrated circuit, digital circuit logic, digital electronic circuits, digital circuit simulation, digital clock circuits, digital circuit detective, digital circuit testing, adder digital circuit, digital vlsi circuits, digital inverter circuit, digital design, digital logic, digital level, digital cmos, logic circuit, digital ic, digital ttl, digital layout, digital schematic, gate circuit, tutorial circuit, digital inputs, digital switching, digital multiplexer, digital circuitry, digital vlsi
|
|
|
|
|
|
analog circuit, analog circuit design, cmos analog circuit design, analog amplifier circuit, analog and rf circuits, analog circuit designers, analog circuit diagram, analog circuit testing, analog digital circuit, analog divider circuit, analog delay circuit, analog comparator circuit, analog input circuit, analog integrated circuits and signal, analog filter circuit, analog output circuit, analog rf circuit, analog switch circuit, cmos analog circuit, voltage circuit, circuit noise, circuit simulation, frequency circuit, phase circuit, resistor circuit, pulse circuit, high voltage circuit, comparator circuit, differential circuit, linear circuit
|
|
|
|
|
|
SIMPLE CIRCUIT:
In the circuit , a 10 V battery is attached to a light bulb of resistance R = 4 ohms.
a.) What will be the current flowing out of the battery?
b.) How much power is dissipated in the resistor? (Tells you how bright it glows.)
c.) Which labelled point in the circuit is at a higher voltage, A or B?
SERIES CIRCUIT:
In the circuit, the same 10 V battery is now attached to two light bulbs in series, each of the same resistance R = 4 ohms.
a.) What is the total resistance of the entire circuit?
b.) What will be the current flowing out of the battery?
c.) How much power will be dissipated in each resistor? (Tells you how bright each glows.)
PARALLEL CIRCUIT:
In the circuit, the same 10 V battery is now attached to two light bulbs in parallel, each of resistance R = 4 ohms.
a.) What is the total resistance of the entire circuit?
b.) What will be the current flowing out of the battery?
c.) How much power will be dissipated in each resistor? (Tells you how bright each glows.)
|
|
|
|
|
|
7.If there is 100 mA of current flowing into a three-branch parallel circuit and two of the branch currents are 40 mA and 20 mA, the third branch current is........
a. 60 mA
b. 40 mA
c. 160 mA
d. 20 mA
8. In the parallel portion of series-parallel circuits, the total resistance is........
a. equal to the smallest resistance
b. less than the smallest resistance
c. less than any one resistance
d. greater than the largest resistance
9. Which one of the statements below does NOT apply to the voltage inducd into a wire when it is moved through a magnetic field?
a. It depends on the current flowing in the wire
b. It depends on the strength of the magnetic field
c. It depends on the speed of wire motion
d. It depends on the length of moving wire in the field
10. The amount of voltage that is induced in a conductor depends on the.......
a. length of time a conductor remains stationary in the magnetic field
b. direction of the current flowing
c. length of the conductor in the magnetic field
d. direction of motion of the conductor in the magnetic field
11. In a two-source circuit, one source alone produces 10 mA through a branch. If the other source alone produces 8 mA in the opposite direction through the same branch, what is the total current through the branch?
a. 18 mA
b. 2 mA
c. 10 mA
d. 8 mA
12. In solving series-parallel circuits, the last and easiest to solve for is......
a. IT
b. PT
c. RT
d. ET
13. An ohmmeter should.......
a. be inserted into the circuit so the current flows through it
b. have the polarity carefully checked before its use
c. be connected across a circuit with the power on
d. be placed across the resistor after the resistor has been disconected from the circuit
14. Add 21 mA and 8000 ua and express the result in milliamperes.
a. 29 mA
b. 218 mA
c. 290 mA
d. 21.8 mA
|
|
|
|
|
|
(a) transient over voltages
(b) a power factor of less than 0.85
(c) fluctuating protective conductor currents
(d) heavy starting currents
|
|
|
|
|
|
1. For automotive work, common wrench sizes range from:
_____ a. 1/8 inch to 5/8 inch (standard) and 6 mm to 60 mm (metric).
_____ b. 1/4 inch to 3/8 inch (standard) and 3 mm to 36 mm (metric).
_____ c. 1/4 inch to 1-7/8 inch (standard) and 6 mm to 40 mm (metric).
_____ d. 1/4 inch to 1-5/8 inch (standard) and 6 mm to 32 mm (metric).
2. If a bolt or nut is stripped, a/an __________ wrench should be used to remove the stripped part?
_____ a. pipe
_____ b. impact
_____ c. adjustable
_____ d. combination
3. When installing an oil filter, you should:
_____ a. use an oil filter wrench.
_____ b. tighten it by hand.
_____ c. tighten it at least 1 ½ turns.
_____ d. turn it counterclockwise one full turn.
4. After cleaning battery terminals, some technicians use a little chassis grease to:
_____ a. insulate the terminals from accidental shorts.
_____ b. seal the terminals and retard corrosion.
_____ c. improve the electrical connection between the terminals and cables.
_____ d. make the terminals easier to remove the next time.
5. The specific gravity, as measured with a hydrometer, of a fully charged cell in a lead-acid automobile battery is:
_____ a. 13.1 to 16.0.
_____ b. 12.6.
_____ c. 7.0.
_____ d. 1.27.
6. If the charging voltage of an automobile electrical system is over 16 volts, the __________ is/are likely to be defective.
_____ a. battery
_____ b. starter
_____ c. voltage regulator
_____ d. battery cables
7. How should an ammeter be connected when checking the load, or current drain, from a battery?
_____ a. Red meter lead to positive battery terminal; black meter lead to disconnected end of positive battery cable
_____ b. Red meter lead to negative battery terminal; black meter lead to positive battery terminal
_____ c. Red meter lead to positive battery terminal; black meter lead to negative battery terminal
_____ d. Black meter lead to negative battery terminal; red meter lead to chassis ground
8. If there is any doubt about what should be added to a cooling system using a new extended-life coolant after testing the specific gravity:
_____ a. flush and refill the system.
_____ b. consult the vehicle owner's manual.
_____ c. add water.
_____ d. add coolant.
9. A vacuum gauge is used to:
_____ a. detect leaks in the cooling system.
_____ b. detect intake and mechanical problems in the valve and piston area of the engine.
_____ c. adjust the flow pattern of fuel injectors.
_____ d. check ring and pinion gear backlash.
10. A good fuel injector should produce a/an:
_____ a. oval spray pattern and remain open after firing.
_____ b. irregular spray pattern and partially close after firing.
_____ c. circular spray pattern and remain open after firing.
_____ d. cone-shaped spray pattern and shut off after firing.
11. When setting the ring and pinion gear backlash of a differential, for greater accuracy, you should:
_____ a. set the clearance between .008" and .010".
_____ b. use a hydraulic press.
_____ c. look up the setting for the specific differential being serviced.
_____ d. use a smaller clearance setting on differentials that run hot.
12. The toe angle is usually set "in at the front," which means that the front tires are:
_____ a. pointing toward each other when viewed from the front.
_____ b. pointing toward each other at the top, inward toward the center of the vehicle.
_____ c. pointing away from each other at the top, outward from the center of the vehicle.
_____ d. perfectly parallel to the vehicle.
13. When removing a shock absorber, a special tool is used to:
_____ a. remove the two bolts at the top.
_____ b. hold the end of the shock while the nut is removed.
_____ c. hold the end of the shock while the upper bolt is removed.
_____ d. remove the nut and two bolts holding the shock in place.
14. A/An __________ is used to correct static and dynamic tire imbalance.
_____ a. drum gauge
_____ b. alignment machine
_____ c. tire balancer
_____ d. tire changer
15. In addition to special brake tools, what regular hand tool is needed to assemble shoe type brakes?
_____ a. A pair of pliers
_____ b. A Phillips-head screwdriver
_____ c. A ball peen hammer
_____ d. A soft face hammer
16. A brake shoe-to-drum gauge is used to:
_____ a. adjust the drum to the circumference of the brake shoes.
_____ b. adjust brake shoes to the diameter of the drum.
_____ c. determine the placement of the brake drum.
_____ d. measure the thickness of the brake drum.
17. A continuity tester is used to check electrical circuits for:
_____ a. improper voltage.
_____ b. insufficient current.
_____ c. excessive current.
_____ d. a broken connection.
18. An ohmmeter is used to check the:
_____ a. voltage in an electrical circuit.
_____ b. amount of resistance in a wire or circuit.
_____ c. amount of current flow in a circuit.
_____ d. amount of power consumed by an electrical device.
19. Most headlights are set:
_____ a. horizontally straight ahead, because the low beams automatically drop lower and to the right.
_____ b. first for the high beams and then for the low beams.
_____ c. low and to the right.
_____ d. low and to the left.
20. The lower (smaller) the gauge number of an electrical wire, the:
_____ a. thinner the wire's insulation.
_____ b. lower the current-carrying capacity of the wire.
_____ c. higher the current-carrying capacity of the wire.
_____ d. smaller the diameter of the conductor.
|
|
|
|
|
|
Two resistors, 35.0 ohms and 64.0 ohms, are connected in parallel. The current through the 64.0 ohm resistor is 3.40 A.
(a) Determine the current in the other resistor.
(b) What is the total power consumed by the two resistors?
Any help is appreciated, I cannot figure out how to solve this without knowing the voltage across the power source????
|
|
|
|
|
|
|
I have been looking at some transmitter circuits and would like to know what determines the output power (Watts). I have seen two similar circuits (same power supply, components) have completely different wattages. For example, the schematic here http://www.electronics-lab.com/projects/... vs the one here http://www.zen22142.zen.co.uk/Circuits/r... There is an 8x difference in power between them, but they both are able to run off of the same voltage. I know basically it is the current that determines power, but to which parts specifically should the current be increased/decreased to increase/decrease wattage?
|
|
|
|
|
|
R3 and R4 are series and R2 is parallel to R3 and R4:
R3 = 3.5 ohms
R4 = 5.5 ohms
R2 = 7 ohms
R1 = 2.50 ohms is the series to the above three resistors.
Volt batt: 12 V
--------------------------------------...
Here is what i did:
Req_1 = 3.5 ohms + 5.5 ohms
Req_1 = 9 ohms
1/Req_2 = 1/9 ohms + 1/ 7 ohms
Req_2 = 3.94 ohms
Req = Req_1 + Req_2
Req = 9 ohms + 3.94 ohms
Req = 13 ohms
Total current provided by battery:
I = V/R
I = 12 V / 13 ohms
I = 0.92 A
So...my quesetion is..what is the current flowing through each resistor R1, R2, R3, R4?
I have to figure out how to find the voltage drop and power dissipated of each as well. But if you can tell me how to find the current of each, then perhaps I can figure out how to find the voltage and power of each as well on my own. However, it would mean so much to me if you could help me a little or throw some hints to find those two. Other than that, I'm just asking how to find the current of each resistor. Thanks!!!!
|
|
|
|
|
|
I'm using 2 circuits, one with 3 LEDs and one with 4 LED's. Led's are rated at 2.6v, 70ma. LED's will be wired in series. Power source is ~13.8v.
Circuit 1
3LEDs in series connected to a 82ohm 1w resistor and a 6.8ohm 1w resistor (resistors in series).
Circuit 2
4LEDs in series connected to a 51ohm 1/2w resistor and a 1.3ohm 1/2w resistor (resistors in series).
Will these give me nominal voltage and current?
|
|
|
|
|
|
|
I am doing a lab and there are two different circuits. One of them is powered by a battery (10V) and the other is powered by a current source (10A). The Voltages in the second circuit were really high and I need to know why that is.
|
|
|
|
|
|
1) As more resistors are added in parallel to a constant voltage source, the power supplied by the source will
a)increase
b)decrease
c)does not vary
d)may increase or decrease depending on the value of the resistors..
if anyone knows can u please explain as well since i have a quiz on this.
2)The current in a single loop circuit that has a reistance R is 3.4A. The current is reduced to 3.1 A when an additional resistance of 4ohm is added in series with R. What is the value of R?
|
|
|
|
|
|
1. which type of circuit has a single conducting path?
2. which type of circuit has mulitple conducting paths?
3. what is the relationship between the power, current, and voltage in a circuit?
4. what are 2 devices that prevent overloaded circuits?
|
|
|
|
|
|
|
I know that it is Cosine of Angle between Voltage & Current. But I want to know its significance.
|
|
|
|
|
|
i have 250 unit of LEDs which i connect 5 IN SERIES and then continue with 50 IN PARALLEL.
Each LEDs spec is :
- 3.6V max
- Current 20mA
- Peak Current 80mA
- Reverse Voltage 5V
- Power Dissipation 100mW
Batteries are using Energizer D Cell Alkaline (12 in series) which has 20500mAH Capacity
Can somebody please tell me how can i count
- Each LEDs Power comsumption (Watt and Ampere).
- Total LEDs Power Consumption (Watt and Ampere).
- How long will the batteries last?
And how can i make this circuit stabilized?
note: i want to light up all 250 LEDs simultaneous.
|
|
|
|
|
|
Can anyone tell me equations for the following subjects
Charge
Resistance
Voltage
Power
Amps (current)
Thanks!
PS (grade 11 physics)
|
|
|
|
|
|
I'm an EE major and something has always bugged me in the (self-chosen) little-as-possible interaction with circuits that I've had:
How can a voltage source be high voltage, low current? More specifically, how can the output current be variable given a specific voltage? Is it not as simple as applying V = IR? Given the R of the load you can find I? If, for example, a power supply limits the current out, how does this not directly limit the voltage out, assuming the same load?
Supposedly power lines use high voltage, but low current to transfer power, and they say touching high voltage lines isn't dangerous, as long as the current is low...how is the current not determined by the resistance of your body??
Please help restore the foundations of my supposedly good education.
|
|
|
|
|
|
For DC power is equal to volts times amps.
For AC things a little more complicated. Because the direction of the voltage and the current are constantly changing is possible for the voltage and the current to be out of phase with each other.
In that case power is equal is volts times amps times the cosine of the phase angle.
The consequences of this are the circuit may not be able to deliver as much power without overheating because the circuit must be able to deliver ALL the current not jsut the current doing useful work.
For some circuits, increasing the voltage (up to a point) can cause a reduction in current (induction motors are a good example).
As a secondary note, a lot of these claims of simple devices improving energy efficiency have to due with people not understanding this concept of phase angle in AC circuits.
|
|
|
|
|
|
voltage is a potential difference between two points, usually in a circuit. you can think of it as analogous to gravity potential...though don't carry that analogy too far or else you get yourself into trouble with energy. electrons/other charged particles will tend to flow from high potential places to low.
current is the amount of charge passing through a surface in a given time; it is usually denoted by dQ/dt.
power, when defined mechanically, is a measure of energy per unit time. your light bulbs are measured in units of power (watts). with electrical circuits, power = IV, which is current times voltage (for relatively simple circuits).
energy is probably the most abstract concept of these. it is...a measure of the ability to do work, to put it sort of vaguely. energy equations in circuits vary depending on your components.
|
|
|
|
|
|
before analysing the below addded part of the concept plz read this
THE MAIN CONCEPT OR THE functionality of the above circuit design is to convert the 50hz supply from the mains to 1hz to drive a clock circuit( many counters to gether :P) therefore the output of 1hz(that is 1 cycle per second) should be achieved within that second and the other 1hz at the next second and so on.
The LS90 is a divide by 5 or 10, so two of these will get you a divide by 50, with a nice 50-50 square wave output. Look at the data sheet for how to connect them.
First you need a something to reduce your 50hz to a 0 to +5 square wave. Use a voltage divider or transformer to get the 50Hz voltage down to about 10 volts. Look up schmidt trigger circuits and comparators. Us that to get the sine wave into a square wave that is suitable to be applied to a LS90.
used MULTISIM.. function generator (5v 50hz square waves) connencted the common to ground and connected the +terminal to clock input 1, shorted the Qa and clock input 2, kept MR1 high and MS2 low (according to datasheet sheet of SN74LS90), got a BCD OUTPUT 0-9 PERFECT, now:- i added a AND gate to the LSB and MSB (1001)(code of nine) so
1)the output which i am getting at the AND gate is divided by 10?
placed another ic
i used the same configuration the change was that to make it a DIVIDE BY 5 didnot short the output to the clck2 i/p. but instead provided the ouput from the AND GATE to the 2input of clock and left the fist clk input open.the remaining connections reset pins are the same. what i get on the output is 5binary codes (the leds blink five times simultaneously) but they are ramdom that is it is not a count from 0 to 4 but its something which changes if i connect the rest pins differently?? i need to have a count from 0 to 4 on this ic so that i can AND the FOUR BINARY code and get a 1 HERTZ SUPPLY AT THE FINAL OUTPUT.
plz also :-
can i make the similar circuit IF CORRECT using a 7490 IC?
and
|
|
|
|
|