Unit 6 (Practice): Review Of Electricity Flashcards
Define ‘static electricity’
Static electricity is the buildup of electric charge on the surface of objects.
What is electric charge?
Electric charge is a physical property of matter that causes it to experience a force when placed in an electromagnetic field.
In general, how does a neutral object become charged?
A neutral object becomes charged by gaining or losing electrons.
Fill in the blanks: Objects with like charges _____
repel each other.
Fill in the blanks: Objects with unlike charges ______
attract each other.
What are three ways an object can become charged?
- Charging by friction
- Charging by contact
- Charging by induction
What is an electroscope? What are the two types of electroscopes?
An electroscope is a device used to detect electric charge. The two types are the gold leaf electroscope and the metal rod electroscope.
What are the two methods of charging by contact?
- Direct contact
- Indirect contact
What is the electrostatic series?
The electrostatic series is a list that ranks materials based on their tendency to gain or lose electrons.
When charging an object by friction, how can you predict what charge the object will become?
You can predict the charge based on its position in the electrostatic series.
What happens to electrons when two objects are charged by friction?
Electrons are transferred from one object to another.
A piece of amber is rubbed with silk. What is the charge on each object afterwards?
Amber becomes negatively charged and silk becomes positively charged.
A piece of acetate is rubbed with wool. What is the charge on each object afterwards?
Acetate becomes positively charged and wool becomes negatively charged.
What is meant by ‘charging by conduction’?
Charging by conduction occurs when a charged object touches a neutral object, transferring charge.
When a charged object comes in contact with a neutral object, how will the electrons move?
Electrons will move from the charged object to the neutral object if the charged object is negative, or from the neutral object to the charged object if it is positive.
What is grounding? What is the symbol for grounding?
Grounding is the process of connecting an object to the Earth to neutralize its charge. The symbol for grounding is a vertical line with three horizontal lines underneath.
If a negative object is connected to the Earth by a ground, what will happen to the electrons?
Electrons will flow from the object to the Earth.
If a positive object is connected to the Earth by a ground, what will happen to the electrons?
Electrons will flow from the Earth to the object.
Does the Earth become charged after grounding? Explain.
No, the Earth does not become charged after grounding because it can absorb or supply a large number of electrons without a significant change in its overall charge.
What is charging by induction?
Charging by induction is the process of charging an object without direct contact.
This involves the influence of a charged object on a neutral object, causing charge separation.
What are the two types of charging by induction?
The two types of charging by induction are temporary induction and permanent induction.
Temporary induction occurs when the inducing charge is removed, while permanent induction involves grounding.
What occurs when a charged object comes close to a neutral object but does not touch it?
An induced charge separation occurs, causing the charges within the neutral object to rearrange.
This leads to one side of the neutral object becoming positively charged and the other negatively charged.
What happens when a negatively charged rod is brought close to a neutral metal leaf electroscope?
The electroscope will have its leaves repel each other due to induced negative charges moving away from the rod.
Diagrams would show the charges on both the rod and electroscope at each stage.
What is permanent induction?
Permanent induction is the process of charging an object by grounding while a charged object is nearby.
This leads to a permanent charge on the object even after the inducing charge is removed.
How is permanent induction different from temporary induction?
Permanent induction results in a lasting charge, while temporary induction results in a charge that disappears once the inducing charge is removed.
What is the difference between a conductor and an insulator?
A conductor allows the flow of electric charge, while an insulator resists it.
Conductors have free electrons, while insulators have tightly bound electrons.
Give two examples of good conductors.
Examples of good conductors include:
* Copper
* Silver
Give two examples of fair conductors.
Examples of fair conductors include:
* Aluminum
* Iron
Give two examples of insulators.
Examples of insulators include:
* Rubber
* Glass
What is lightning?
Lightning is a discharge of electricity in the atmosphere, typically during a thunderstorm.
What happens to the particles of water and ice in a thunderstorm as they are hit by winds?
The particles are moved and collide, leading to charge separation within the cloud.
What charge collects at the bottom of the cloud?
Negative charge collects at the bottom of the cloud.
What charge collects at the top of the cloud?
Positive charge collects at the top of the cloud.
What charge will be found on the surface of the Earth as a result of the charge at the bottom of the cloud?
Positive charge will be found on the surface of the Earth.
Why are the electrons pulled to the ground?
Electrons are pulled to the ground due to the attraction of the positive charge on the Earth’s surface.
Explain the function of a lightning rod.
A lightning rod provides a conductive path for lightning to safely reach the ground.