# Answers review guide unit 2  2013 in smart.notebook

```Answers review guide unit 2 2013 in smart.notebook
less brightness/
slows down
decreases current
less brightness/
slows down
decreases current
decreases slightly decreases slightly
(not very noticably) (not very noticably)
turns either on
for a short period
of time (less than
1 min) when charging
or being used)
by itself: turns on a fan or battery.
when against other batteries: acts like a resistor.
Will steadily decrease Decreases: when batteris put against it
while charging
Will go opposite direction Increases current when in same direction as it.
when being used/
Will deplete down to
zero
Decreases: when batteris put against it
Increases current when in same direction as it.
one both both both direction
directions directions
directions
no
no
yes, when
charged
yes
saftey lights, wind­up toys anything that toaster,
most devices stop lights back up power uses electrical energy
Problems to practice:
What is the only way that you can test the difference between the resistor and diode in circuits A & B? You need to test the device with the wires hooked up both ways. Try it once one way, then flip it. If it works both ways and resists ­ its a resistor. If it only works one way and resists­its a diode.
A
B
Example Situation: What happened in the circuit below, from the I turn the switch on in a circuit time it started to 1 minute later? which has a volt reading of 2 Start
1 minute later
volts and 100 mA. It also has a dim lightbulb and device X. 0 mA
200mA
Then I remove device X, and my circuit now has 300 mA, 2 volts and a bright lightbulb.
Stopped
Fast
What was device X? It must be a resistor or a diode, After the circuit started, the ammeter because it lowered the mA decreased to zero mA and the fan reading and the brightness stopped, but is still connected to the of the bulb. You would have batteries and the capacitor. The only explanation is that the capacitor has to test the device X both ways to figure out if it was a filled up with energy and has stopped diode or a resistor, because the flow of energy to the fan and ammeter. You could put a voltmeter they both resist energy.
on the capacitor to confirm this. Answers review guide unit 2 2013 in smart.notebook
A. This device when hooked up to the circuit has a slow fan speed, low ammeter reading, and a low but constant volt reading. It does not
work when I flip the wires. _Diode_________?
B. This device when hooked to the circuit doesn't
allow the circuit to work when I hook up to it either way. It has a volt reading. But when I take the batteries Battery
out of the loop and reconnect the wires to the device, the ammeter goes up and then down to zero. The fan Diode
starts, but then slowly dies. _Capacitor___?
Resistor
Capacitor
C. This Device does the same thing as Letter A, but it works
in both directions. __Resistor____?
D.This device when hooked up to the circuit at the right
actually speeds up the fan and makes the mA go up when
hooked up to the device. When switched, all measurements
go down, but still work. __Battery___?
Other Notes on following slides & similar information
&
Materials to study for quiz from slides 1­3 on test for sure
Answers review guide unit 2 2013 in smart.notebook
Mystery Box Structure
p. 3
Resistor
-Reduces the current (mA decreases)
-Will slow device or make a bulb dim
-Delivers less power to a device
-Energy can flow through the resistor
in both directions.
-Is not an energy source
-Increase in temperarture of the
reistor = more resistance of energy.
Answers review guide unit 2 2013 in smart.notebook
Questions you should be able to answer for a resistor:
1. Is it an energy source? (can you hook it up to a device and it will turn on?) NO
2. Is the device able to function in both directions? (can you hook it up left to right & right to left?) YES
3. Does it reduce the amount of energy flowing to a device? (amount of Amps /Volts / Brightness/Fan Speed?) Yes, it lowers mA, brightness, and fan speed.
4. What makes this device different from other similar devices? The resistor resists like a diode, but is able to function in both directions.
p. 6
What it does: Diode
-Energy can flow through the diode in one direction.
(one way) Neg (-) to Pos (+)
-Reduces the current (mA decreases)
-Will slow device or make a bulb dim
-Is not an energy source
-LED's have lights that turn on when energy passes
through them. Other diodes don't, so you need a
device or check the mA if on or not.
Answers review guide unit 2 2013 in smart.notebook
Questions you should be able to answer for a diode:
1. Is it an energy source? (can you hook it up to a device and it will turn on?) NO
2. Is the device able to function in both directions? (can you hook it up left to right & right to left?) No
3. Does it reduce the amount of energy flowing to a device? (amount of Amps /Volts / Brightness/Fan Speed?) Yes, it lowers mA, brightness, and fan speed.
4. What makes this device different from other similar devices? The diode resists, but is able to work like a one way switch. It only functions when inserted in the 1 direction.
p. 7
Capacitor
What it does:
-Charges or Discharges a limited amount of energy
(stores energy, does not generate it)
-Discharges its stored energy when hooked to a
circuit (with a device) in the opposite direction it
was charged with energy.
-Can show volt readings by itself when charged.
-Device will turn on for short amount of time, then
stop functioning.
-Will empty of energy or fill with energy in a short
period of time.
Answers review guide unit 2 2013 in smart.notebook
Questions you should be able to answer for a capacitor:
1. Is it an energy source? (can you hook it up to a device and it will turn on?) Yes, it is a temporary energy source. When charged, itwill give a volt reading, mA reading, & provide energy to a device.
2. Is the device able to function in both directions? (can you hook it up left to right & right to left?) Yes.The energy enters in one direction and exits the opposite direction. The capacitor can be turned,but then entering and exiting are reversed.
3. Does it reduce the amount of energy flowing to a device? (amount of Amps /Volts / Brightness/Fan Speed?) No. But as it fills it lowers the mA and brightness/fan speed & the volts go up on the capacitor. When emptying, mA go backwards & slowly lowers the brightness/fan speed & volts decrease.
4. What makes this device different from other similar devices? Example: How is a capacitor different than a battery? The energy supply is only temporary. Once the capacitor fills up, no more energy passes through the circuit. Also, as the energy exits the capacitor, it takes a short amount of time to empty and all devices stop functioning or read 0.
p. 9
Single Cell Battery
What it does:
-Is an energy source
-Will give a volt reading by itself
-Will give an ammeter reading when hooked
in a circuit with a device
-The energy does not build up or decrease
in a short period of time
-Has a negative and positive terminal (side).
Answers review guide unit 2 2013 in smart.notebook
Questions you should be able to answer for a single cell battery:
1. Is it an energy source? (can you hook it up to a device and it will turn on?) YES! When a device and measuring tool are connected correctly, it will give a long lasting/unchanging measurement and power a device at a constant rate.
2. Is the device able to function in both directions? (can you hook it up left to right & right to left?) ­If another battery is hooked with it no. ­If just a device or a measuring tool are connected to it, the yes.
3. Does it reduce the amount of energy flowing to a device? (amount of Amps /Volts / Brightness/Fan Speed?) No. If hooked up in series with another battery, it will increase all measurements.
4. What makes this device different from other similar devices? Example: How is a battery different than a capacitor? A battery will not have changing volt and mA readings. The light or fan will stay constant. While a capacitor will change the volt, mA, and rate of devices in less than 1 minute.
Before flip: Ammeter = 370 mA
Fan = clockwise
After flip: Ammeter = 0 mA
Fan = Not moving
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