Out of these items, which are an analog device and which are digital devices?

Question

1. On/Off Switch
2. Potentiometer
3. Classroom Clock
4. The timer on a microwave oven
5. Mercury thermometer
6. A phototransister
7. A photocell
8. Lock on a car door
9. Character on a keyboard
10. Wattmeter at your house

Answer 1

Something digital has distinct (i.e., discrete) states. An on/off switch has 2 distinct states and is therefore digital. Something analog has an infinite number of states. A mercury thermometer has an infinite number of states, as the mercury expands and contracts fluidly to tell the temperaure.

Answer 2

A number of these could be considered either!!

1. On - Off wall switch, not only digital, but binary
2. Potentiometer, by design can set dc voltages to very fine resolution making it analog.
3. Classroom Clock. Tricky. The dial reading mechanism (big hand/little hand) is clearly analog in function. However it is not uncommon for the clock in a classroom to be part of a master time system that is synchronized digitally. aka as IBM clocks.
4. The heating element in the microwave is digital, it runs either full on or is off. The % adjustment actually is a time ratio between these two states, so half power really means full power half the time. It is quite common for older MW ovens to have an analog timer mechanism that you set by turning a dial, just like the typical toaster oven.
5. Thermometer is full analog in operation and reading
6. Photocell transistor, action depends on the circuit set up, but usual application is for it to latch in either "active" or "dark" states, the amplification of the transistor making the transition a sharp distinction. However the phototransistor is also used in some analog circuits where high speed operation is needed as ordinary photocells tend to have a sluggish response and latency characteristic.
7. photocell or photoresistor is analog with the resistance or current continuously varying depending on illumination. used in motion detectors and talkie movie soundtracks.
8. a key lock is digital, but not binary. usually 4 or 5 depths cut into the key are used to actuate the tumbler sequence.
9. keyboard is just another form of electrical switch, digital
10. Old fashioned, this was analog with gears and wheels. modern versions tally digitally, and in some cases can transmit digitally the reading back to the electric company office, no "meter reader" needed any more.

Answer 3

1. Digital
2. Analog
3. Analog
4. Digital
5. Analog
6. Digital
7. Analog
8. Digital
9. Digital
10. Analog

Answer 4

all of them can be analog and digital devices together , exept potentiometer.it mean you can make them with analog and digital devices. for example ICs are digital devices.

Answer 5

I think they are all analog at least they could be.