Electric current is a flow of charge
Review!
What is ELECTRIC POTENTIAL ENERGY? ______
______.
Electrical potential energy is measured in ______
If particles close to each other have the same charge, there is stored energy because ______
______.
A charge will NOT move ______
______.
There must be a DIFFERENCE in ______
______.
The greater the potential difference, ______
______.
When an electrical charge moves from a higher potential to a lower potential, ______
______.
Resistance depends on:
-______
-______
-______
(______)
Page 652.
What is electric current (I)? ______
______.
Page 653.
Electric current obeys the same rules as moving static charges:
-______
-______
The difference between moving static charges and current: ______.
What is an ampere (amp) (A)? ______
______
Relationship between current, voltage and resistance.
The current in a wire is determined by ______.
______is another word for ______
______.
You can think of ______as the pressure pushing the ______.
Remember, the ______the ______, the ______the ______.
Resistance is ______
______.
Resistance is expressed in ______.
You can think of resistance as ______.
The higher the resistance, the ______the current.
Page 655.
What is an electric cell? ______
______.
Technically, a battery is two or more cells connected to each other, but some single cells (such as C cells and D cells) are often called batteries.
Read page 656.
Primary CellsStorage Cells
Solar cells:
Ohm’s Law Calculations. For each of the following, write the equation, show your work, include units, and circle your final answer.
1.A walkman uses a standard 1.5 V battery. How much resistance is in the circuit if it uses a current of 0.01 A?
2. What current flows through a hair dryer plugged into a 110 Volt circuit if it has a resistance of 25 ohms?
3. A 12 Volt car battery pushes charge through the headlight circuit resistance of 10 ohms. How much current is passing through the circuit?
4. An electric heater works by passing a current of 100 A though a coiled metal wire, making it red hot. If the resistance of the wire is 1.1 ohms, what voltage must be applied to it?
5. A subwoofer needs a household voltage of 110 V to push a current of 5.5 A through its coil (circuit).
What is the resistance of the subwoofer?
6. A light bulb has a resistance of 5 ohms and a maximum current of 10 A. How much voltage can be applied before the bulb will break?
7. How much current is in a circuit that includes a 9-volt battery and a bulb with a resistance of 3 ohms?
9. How much current is in a circuit that includes a 9-volt battery and a bulb with a resistance of 12 ohms?
10. A circuit contains a 1.5 volt battery and a bulb with a resistance of 3 ohms. Calculate the current.
11. A circuit contains two 1.5 volt batteries and a bulb with a resistance of 3 ohms. Calculate the current. (Hint: add the battery voltage)3.
3
12. What is the voltage of a circuit with 15 amps of current and toaster with 8 ohms of resistance?
13. A light bulb has a resistance of 4 ohms and a current of 2 A. What is the voltage across the bulb?
14. How much voltage would be necessary to generate 10 amps of current in a circuit that has 5 ohms of resistance?
15. How many ohms of resistance must be present in a circuit that has 120 volts and a current of 10 amps?