Sci I - Electrons and Protons

What is Franklin’s “electrical fire” actually?

Electrically charged particles moving from atom to atom.

What are atoms composed of?

Three different types of particles.

In physics, what is a particle?

A fundamental piece of matter of which everything else is made.

What analogy is used to visualize atoms?

A miniature version of the solar system.

What is at the center of an atom?

The nucleus.

What is the nucleus composed of?

Protons and neutrons.

What is one similarity between protons and neutrons?

They both have nearly the same mass.

What is mass?

A fundamental quantity of nature, measured in kilograms (kg), determining an object’s response to forces.

What is the mass of one kilogram approximately equal to?

The mass of one liter of water.

What is the mass of a typical adult human?

About 60 to 70 kg.

What is another term sometimes used for mass?

Inertia, or resistance to changes in motion.

What is the third type of particle in an atom?

The electron.

Where are electrons located in an atom?

Far outside the nucleus, orbiting around it.

How do electrons orbit the nucleus?

Similar to how planets orbit the Sun.

How many protons and electrons does hydrogen usually have?

One proton in the nucleus and one electron orbiting it.

How many protons and electrons does oxygen usually have?

Eight protons in the nucleus and eight electrons orbiting it.

What defines an element?

Its number of protons.

Does an oxygen atom with an extra electron still count as oxygen?

Yes, because the element is defined by its number of protons.

Which particle’s movement is primarily involved in electricity?

Electrons.

Do protons play a role in electricity?

Yes, but electricity primarily involves electrons.

Do neutrons play a role in electricity?

No, neutrons are electrically neutral.

What does it mean that neutrons are electrically neutral?

They have no electric charge.

What is electric charge?

A fundamental quantity of particles, similar to mass.

Can the amount of charge on a particle be zero?

Yes, such as with a neutron.

Which particles have electric charge?

Protons and electrons.

How do the charges of protons and electrons compare?

They are equal in amount but opposite in type.

What is the charge of a proton called?

Positive.

What is the charge of an electron called?

Negative.

What happens between oppositely charged particles?

They attract each other.

What happens between particles with the same charge?

They repel each other.

What force keeps electrons in orbit around protons in the nucleus?

The attraction between opposite charges of protons and electrons.

If protons and electrons have the same amount of charge, why does electricity mainly involve electrons?

Because electrons experience much greater acceleration due to their smaller mass.

Why do electrons orbit the nucleus instead of the nucleus orbiting electrons?

Because of differences in inertia and forces, similar to why the Earth orbits the Sun.

What does Isaac Newton’s first law of motion state?

An object’s inertia will allow it to keep going unless forces stop it.

What is the unit of force?

The newton.

What is one newton approximately equal to?

About the weight of an apple.

What does “forces” refer to?

Interactions between objects that change each other’s motion.

What does Newton’s second law of motion state?

An object feeling a force will accelerate in the direction of that force.

What does more force cause according to Newton’s second law?

More acceleration.

What happens when the same force is applied to objects of different masses?

The object with more mass will accelerate less.

Which accelerates faster under the same force: a small car or a large truck?

A small car.

What does Newton’s third law of motion state?

Every action has an equivalent reaction.

If object A exerts a force on object B, what happens according to Newton’s third law?

Object B exerts the same force back on object A.

What pulls on the Earth according to Newton’s law?

The Sun’s gravitational pull.

What pulls on the Sun according to Newton’s law?

The Earth’s gravitational pull.

Why does the Earth accelerate more than the Sun?

Because the Earth has much less mass than the Sun.

Does the Sun accelerate at all from the Earth’s pull?

Yes, but only a tiny amount compared to the Earth’s motion.

How are protons and electrons pulled by their electrical attraction?

Equally, since they have the same amount of charge.

Why do protons and electrons experience different accelerations?

Because a proton has over a thousand times the mass of an electron.

For the same force, which accelerates more: a proton or an electron?

An electron.

What happens to electrons inside an atom compared to the nucleus?

Electrons are flung around while the nucleus stays relatively stationary.

What analogy explains electron and proton motion?

A parent swinging a child; the child makes a much bigger circle than the parent.

Are protons and neutrons truly fundamental particles?

No, they are made of smaller particles called quarks.

What are quarks?

Smaller fundamental particles that make up protons and neutrons.

When do scientists need to model protons as quarks?

When explaining nuclear reactions.

How should protons be treated in this guide?

As fundamental particles.

Are electrons truly fundamental?

As far as we can tell, yes.