PRE-IB Science 9 Flashcards
What are the two types of electricity?
Static and Current
What is static electricity?
Static electricity is an excess of positive or negative charges on an object.
What are the components of an atom?
Protons, Neutrons, and Electrons
What happens to an atom when it gains electrons?
It becomes a negative ion.
What happens to an atom when it loses electrons?
It becomes a positive ion.
What is the charge on acetate when rubbed with cotton or paper?
Negative charge
What is the charge on vinyl when rubbed with wool or fur?
Positive charge
What are the basic rules of static electricity?
- Gain of electrons ==> Negative charge
- Loss of electrons ==> Positive charge
- Like charges repel
- Opposite charges attract
What does the degree of static interactions between objects depend on?
- The amount of charge
- The distance between charges
How can static electricity be formed?
By rubbing two objects against each other.
What is a key factor that leads to a static electrical charge difference?
The relative difference of charge between two objects.
What does ‘static electricity’ mean?
A charge that can be collected and held in one place.
What is the measurement unit for electric charge?
Coulombs (C)
What can a lightning bolt carry in terms of charge?
5 to 25 C of charge.
What is grounding?
The process that transfers any excess static charge to the ground.
What are some applications of static electricity?
- Plastic sandwich wrap
- Air filters / ionizers
- Painting automobiles
- Photocopiers
What is an electroscope used for?
To detect static charge.
What happens to the metal foil in an electroscope when it becomes charged?
Its sides repel each other.
What is the term for charging an object without touching it?
Induction
What occurs when a charged object is brought near the metal ball of an electroscope?
It induces an electric charge in the ball.
Fill in the blank: A spark caused by a build-up of static charge could cause an ______.
Explosion
True or False: Static electricity can be dangerous and release tremendous amounts of energy.
True
What is the effect of distance on the repulsion between like charges?
Repulsion decreases as distance increases.
What type of materials allow electrons to move freely?
Conductors
What type of materials do not allow electrons to move freely?
Insulators (non-conductors)
What is an induced charge?
A charge formed when electrons are forced to one side of a neutral object, causing polarization.
