Electricity and Charged Particles

Flashcards based on lecture notes about electricity and charged particles.

What is the mysterious force observed when rubbing certain materials together?

The force first dubbed the 'electric force' by William Gilbert in 1600.

What were the four basic elements that Western thought believed all things on Earth were made of?

Earth, air, fire, and water.

What elements is water made of?

Hydrogen and oxygen.

What is the Periodic Table?

A table of all the different kinds of atoms we refer to as elements.

In Greek, what does the word 'atom' mean?

Indivisible.

Besides being a founding father of the United States, what else was Benjamin Franklin known for?

He helped draft the Declaration of Independence and promoted it across Europe.

What is a Leyden jar?

A device that can store electricity and deliver an electric shock to anyone who touches it.

What important discovery did Benjamin Franklin make regarding electric charge?

Electric charge is conserved, meaning it cannot be created or destroyed but merely moved between objects.

What was the purpose of Benjamin Franklin's kite experiment?

He measured the static electricity buildup on a key attached to a kite during a thunderstorm, proving that lightning was an electrical phenomenon.

What is 'electrical fire' actually composed of?

Electrically charged particles moving from atom to atom.

What are the three types of particles that compose atoms?

Protons, neutrons, and electrons.

What is at the center of every atom?

The nucleus.

What two types of particles make up the nucleus?

Protons and neutrons.

What unit is mass measured in?

Kilograms (kg).

What is inertia?

Resistance to changes in motion.

What defines an element?

The number of protons.

What role do neutrons play in electricity?

Electrically neutral and do not have any electric charge.

What is the charge of a proton?

Positive.

What is the charge of an electron?

Negative.

What happens when two protons get near each other?

They repel each other.

What happens when a proton and an electron get near each other?

They attract each other.

When protons and electrons are pulled equally by their electrical attraction, which particle experiences greater acceleration?

The electrons will experience a much greater acceleration.

What are protons and neutrons made of?

They are made of even smaller fundamental particles known as quarks.

What is scientific notation?

A way to write numbers that are both very big and very small in a compact abbreviated form.

What does a negative exponent mean in scientific notation?

Dividing by 10.

What does it mean for something to be a constant?

That it is the same number in every calculation.

What three variables does the strength of the force of gravity depend on?

The masses of the two objects and the distance between them.

When two variables are directly proportional, what does this mean?

Changing one will change the other the same way.

How does distance affect the gravitational force between objects?

The force of attraction between objects getting weaker as the objects get further apart.

What does an inverse square law describe?

A quantity that is inversely proportional to the distance squared.

What is the mass of the Earth?

6 × 10^24 kg.

What are two of the fundamental forces that happen only within the nucleus?

The strong and weak nuclear forces.

What does the strong nuclear force do?

Keeps the protons within the nucleus.

What does the weak nuclear force do?

Transforms particles into other particles and is primarily involved in radioactive decay.

What variables are used in Coulomb's law?

The charges on the two objects (measured in coulombs), their distance apart, and the Coulomb constant.

Who discovered Coulomb's Law?

Charles Coulomb in 1785.

What is the charge of a proton or electron?

±1.7 × 10–19 coulombs.

What does it mean for charge to be quantized?

It comes in discrete, countable amounts.

In the equation for Coulomb's Law, what role does charge play as it relates to the equation for gravitational force?

Charge plays the role that mass plays.

How does gravity differ from the electric force?

Gravity is only attractive.

What is the Coulomb constant (k)?

8.99 × 10^9 N m^2/C^2.

Between two electrons, which force is stronger, the electric force or gravity?

The electric force is far stronger.

Why don't we feel electric forces in our daily lives?

The atom's total charge is zero.

When cloth picks up a negative charge after being rubbed against a glass rod, what has happened?

It has stolen some of the glass rod's electrons.

When cloth picks up a negative charge, what happens to its mass?

The cloth has technically increased in mass.

What is a field in physics?

A numerical value to every point in space due to some phenomenon.

What is a vector?

Has both magnitude and direction.

What is a scalar?

Has no direction.

How can the force of gravity equation be written in abbreviated form, when including the gravitational field constant?

mg.

What does the electric field (E) indicate?

The electric field E (measured in newtons per coulomb) indicates how much force a particle with charge q will feel at that location.