Test review - V, A, Ohmns, power, efficient, cost, etc Flashcards
2 types of chemicals in electrochemical cells
Electrolyte- is a liquid or paste that conducts because it contains ions, wet cell has a liquid electrolyte (ex cars), dry cell has a past electrolyte (ex flashlight and watch)
Electrodes- are metal stripes that react with the electrolyte. 2 diff electrodes are used in better use-zinc and copper
What are electrochemical cells?
A battery is a combination of electrochemical cells. Each of these cells is a package of chemicals (electrode and electrolyte) that concerts chemical energy into electrical energy which is stored in charged particles.
How do we measure voltage?
We use a voltmeter and it’s measured in volts (V)
What is potential difference?
The difference in electrical potential energy between two points that will cause current to flow in the close circuit is called potential difference. It is the strength of the push on the electric current.
The different causes current to flow in a closed circuit. The higher the voltage the greater the energy of each electron.
Voltage (V)- Series vs Parallel
Series:
VT=V1+V2+V3
Parallel:
VT=V1=V2=V3
What is potential energy?
It is energy stored up in an object. A battery has chemical potential energy and electrolyte in its electrochemical cells. Chemicals in the electrolyte react with the electrode. This causes a difference in the amount of electrons between the two terminals. One terminal has many negative charges which are electrons and the other has a nearly positive charges. The conductor is attached to both terminals the electrons can float from the negative terminal to the positive terminal.
How is current measured?
Using an ammeter
Measured in amps(A)
Current (A) Series vs Parallel
Series:
IT=I1=I2=I3
parallel:
IT=I1+I2+I3
How to measure resistance
Using an ommeter
Measured in ohms
Factors affecting resistance
- Material
- Temperature (hotter=higher resistance, cooler=lower)
- Length- (longer=higher, shorter=lower)
(Thinner=higher, wider =lower) - Cross-sectional area
Good conductor=lower resistance
Copper=higher then silver
Resistance (R) Series vs Parallel
Series:
RT=R1+R2+R3
Parallel:
1/RT=1/R1+1/R2+1/R3
What is ohms law?
A law and science is a generalize station based on a collection of observable evidence that can be repeated over many years. Ohms law is the relationship between potential difference (V), Current (I) and Resistance (O)
How do you connect an ammeter
Always connect the negative terminal (black) bracket of the metre to the negative terminal of the source always connect the pause the terminal (red) of the metre to the positive terminal of the source always had an ammeter in series.
How do you connect a voltmeter
Faccting of voltmeter you always add a voltmeter in parallel.
What does resistors do?
Resistors or loads convert Connecticut energy into other kinds of energy (usually heat). Electrons have a higher potential difference when they enter a resistor then when they leave. The more resistance a component has the smaller its conductivity.
