Electricity Flashcards
What charge is on an object if you remove electrons or added
Remove electrons from an object and the object is positive.
Add extra electrons to an object and the object is negative.
How do you remove or add electrons to an object
Friction
Explain the method to the experiment to demonstrate the force between charged objects
Rub a polythene rod with a woollen cloth and then hang it from a clamp (polythene rod is negatively charged.)
Rub a Perspex rod with a woollen cloth. (Perspex rod is positively charged.)
Bring the Perspex rod near the polythene rod.
Now rub another polythene rod with a woolen cloth and bring near to the hanging polythene rod
What conclusion can be drawn from the results of the experiment to demonstrate the force between charged objects
Like charged objects repel each other.
Oppositely charged objects attract each other.
Explain an insulator of electricity
A material through which charge cannot flow.
Explain a conductor in terms of electricty
A material a charge can travel along.
Explain how a lightning rod works
A lightning rod is made of a good conducting metal. A sharp, metal rod is placed above the tallest part of the building. If lightning hits the metal rod, the electrons travel to the ground along the metal conductor and the building is undamaged.
What is current measured in?
Current is measured in the ampere (A)
Explain current electricity
Current electricity is the flow of electrons along a wire.
Explain voltage
Voltage is a measure of the ability of the electrons to do a particular task.
What is another name for voltage
Potential difference
What is the unit of voltage
Voltage is measured in the volt (V).
Explain resistance
The opposition to the flow of electrons is called resistance.
What is the measure of resistance
Resistance is measured in the
ohm, Ω.
How would you set up a circuit to test electrical conduction in a variety of materials and classify each material as a conductor or insulator
Set up circuit with switch,6V battery, light bulb, space to place varying material in.
Name some substances you could test the electrical conduction in and classify each as a conductor or insulator
metal key, iron nail, steel wool, piece of wood, piece of plastic and glass
How would you set up a circuit for the experiment To measure current, potential difference (voltage) and resistance and to establish the relationship between them (Ohm’s law)
Using 6V battery, ammeter, voltmeter, resistor, variable resistor and connecting wires
State Ohm’s law
The potential difference (voltage) is directly proportional to the current. This is called Ohm’s law.
What is the triangle to remeber formula for voltage, current and resistance
Valeries instant rice
V
——-
I x R
Explain the circuit if two bulbs in parallel and the results of taking out a bulb at a time
The current from the battery divides, some passing through one bulb and the rest passing through the second bulb. If the bulbs are identical the current divides into two equals amounts. Each bulb would then get the same current. If one bulb is taken out the other bulb will light.
