science number 2

What revolutionized home appliances in the 1920s?

Electrification enabled the use of new appliances such as toasters, refrigerators, vacuum cleaners, and washing machines.

How did electricity transform communication in the 1920s?

The radio became widely popular, bringing music, news, and entertainment into millions of homes.

What was the Carrington Event?

A powerful burst of plasma from the Sun in 1859 that caused widespread telegraph failures and visible auroras as far south as the tropics.

What were the effects of the Carrington Event on telegraph systems?

Telegraph systems across the United States experienced failures, and some wires caught fire due to electromagnetic disruption.

What percentage of manufacturing was electrified in 1914 compared to 1929?

In 1914, 30% was electrified; by 1929, it had risen to 70%.

How did electricity impact productivity in industry during the 1920s?

It enabled more precise machinery, improved factory lighting, and supported mass production of goods like automobiles.

What is the significance of electricity in contemporary life?

Electricity is a cornerstone of modern life, powering homes and global communication networks.

When did scientists begin to understand the nature of electricity?

In the 19th century.

What does this Science Resource Guide aim to explore?

Humanity's journey to understand and master electricity, including its role in binding atoms and creating electromagnetic waves.

What is the relationship between electricity and Einstein's theory of relativity?

Electricity influenced Einstein's theory, revealing it as a fundamental key to understanding the universe.

What was the percentage of American homes with electricity at the beginning of the 1920s?

Only 30% of American homes had electricity.

What is the role of Earth's magnetic field during solar events?

It typically protects the planet from solar phenomena like coronal mass ejections.

What are some examples of bold-faced terms in the resource guide?

These terms are defined in the glossary or appendix of units and constants at the end of the guide.

What is the main focus of Section I in the resource guide?

Electricity, including charged particles and their historical context.

What phenomenon occurs when certain materials are rubbed together?

They can pick up small, lightweight objects due to static electricity.

What is the significance of the decade of the 1920s in American history?

It marked a turning point in the electrification of daily life.

What are some applications of electromagnetic waves mentioned in the guide?

Applications include long-distance communication, radio, television, LEDs, and solar power.

What is Ohm's Law?

A fundamental principle that relates voltage, current, and resistance in electrical circuits.

What is the purpose of transformers in electrical systems?

Transformers are used to change the voltage of electricity for transmission and distribution.

What is the concept of circuit resonance?

A phenomenon that occurs in electrical circuits when the inductive and capacitive reactances are equal.

What is the role of capacitors in electrical circuits?

Capacitors store and release electrical energy in circuits.

What is the significance of the speed of light in electromagnetic waves?

It is a fundamental constant that determines the propagation speed of electromagnetic waves.

What does the term 'electric polarization' refer to?

The separation of charges within an object, leading to an induced electric field.

What are conductors and insulators?

Conductors allow electricity to flow easily, while insulators resist the flow of electricity.

What is the importance of the electrical grid?

It is essential for the distribution of electricity across regions to homes and businesses.

What percentage of American homes had electricity at the beginning of the decade?

30%

Who first dubbed the term 'electric force'?

William Gilbert in 1600

What is the Greek word for amber, which is related to electricity?

Electron

What did ancient philosophers believe all matter was made of?

Four basic elements: earth, air, fire, and water

What is the modern understanding of elements compared to historical beliefs?

Elements are made of atoms, which are not truly fundamental as they can be divided into smaller particles.

What does the term 'atom' mean in Greek?

Indivisible

What discovery did Benjamin Franklin make regarding electric charge?

Electric charge is conserved; it cannot be created or destroyed, only moved.

What device did Franklin experiment with that can store electricity?

Leyden jar

What was Franklin's famous experiment involving kites meant to prove?

That lightning is an electrical phenomenon.

What are the three types of particles that make up an atom?

Protons, neutrons, and electrons.

Where are protons and neutrons located within an atom?

In the nucleus.

What is the mass comparison between protons and neutrons?

Both have nearly the same mass.

What is the typical mass of an adult human?

About 60 to 70 kg.

What is the role of electrons in electricity?

Electrons are primarily responsible for electricity through their movement.

How many protons and electrons does a hydrogen atom have?

One proton and typically one electron.

How many protons and electrons does an oxygen atom have?

Eight protons and typically eight electrons.

What is the charge of neutrons?

Neutrons are electrically neutral and have no charge.

What does mass refer to in terms of physics?

A fundamental quantity that determines an object's response to forces.

What is the significance of the Periodic Table?

It lists all the different kinds of atoms referred to as elements.

What is the basic model of an atom compared to?

A miniature version of the solar system.

What happens when you rub certain materials together?

They become electrically charged and can attract small objects.

What did Franklin's experiments reveal about the nature of electricity?

He discovered that certain objects could attract or repel each other based on their electric charge.

What is the fundamental quantity of electric charge?

It is a property of particles, similar to mass.

What are the two types of electric charge?

Positive (protons) and negative (electrons).

What happens when two objects with the same charge interact?

They repel each other.

What happens when two objects with opposite charges interact?

They attract each other.

What keeps electrons in orbit around protons?

The attraction between oppositely charged particles.

According to Newton's first law of motion, what will an object in motion do?

It will continue in motion unless acted upon by an external force.

How is force measured in physics?

In newtons.

What does Newton's second law of motion state?

An object will accelerate in the direction of the force applied to it; more force means more acceleration.

Why do heavier objects accelerate less than lighter ones when the same force is applied?

Objects with more mass have greater resistance to acceleration.

What does Newton's third law of motion state?

For every action, there is an equal and opposite reaction.

Why do protons and electrons experience different accelerations despite having the same charge?

Protons have over a thousand times the mass of electrons, resulting in less acceleration for protons.

What are quarks?

Smaller fundamental particles that make up protons and neutrons.

What is scientific notation?

A way to express very large or very small numbers in a compact form using powers of ten.

How is the mass of the Sun expressed in scientific notation?

Approximately 2 × 10^30 kg.

What is the mass of a single proton in scientific notation?

1 × 10^-27 kg.

What does the prefix 'kilo-' mean in the metric system?

1,000 times the base unit.

What is the value of the prefix 'milli-'?

0.001 or 10^-3.

What is the strong nuclear force responsible for?

Keeping protons and neutrons within the nucleus.

What is the weak nuclear force?

A fundamental force that plays a role in nuclear decay processes.

What is the role of electric force in atomic structure?

It attracts and repels charged particles, keeping atoms together.

What is inertia?

The tendency of an object to resist changes in its state of motion.

What is the relationship between force and acceleration?

More force results in greater acceleration, according to Newton's second law.

What happens when a skater pushes against a wall?

The wall pushes back with an equal and opposite force.

Why do the Earth and the Sun not equally accelerate toward each other despite their gravitational attraction?

The Earth has much less mass than the Sun, resulting in greater acceleration for the Earth.

What is the significance of modeling in science?

Models approximate reality and help explain observations, even if they are not perfectly accurate.

What role does the weak nuclear force play?

It transforms particles into other particles and is primarily involved in radioactive decay.

How does gravity function?

Gravity pulls mass toward other mass, with its strength depending on the masses involved and their distance apart.

What is the equation for gravitational force?

FG = G(m1m2/r²), where m1 and m2 are the masses, r is the distance between them, and G is the gravitational constant.

How does gravitational force change with mass?

The gravitational force is directly proportional to the masses; as mass increases, gravitational force increases.

What happens to gravitational force as distance increases?

Gravitational force decreases; specifically, it follows an inverse square law, meaning doubling the distance reduces the force to one-fourth.

What is the gravitational constant (G)?

G is a constant value of 6.67 × 10⁻¹¹ N m²/kg², used in calculating gravitational force.

Why is gravity between small masses negligible?

The gravitational force between small masses, like particles within an atom, is extremely small due to the tiny value of G.

What is Coulomb's Law?

Coulomb's Law describes the electric force between charged objects: FE = k(q1q2/r²), where q1 and q2 are charges, r is the distance, and k is the Coulomb constant.

What does Coulomb's Law reveal about electric forces?

Electric forces depend on the amount of charge and the square of the distance between charged objects.

How does charge compare to mass in terms of fundamental forces?

In Coulomb's Law, charge plays the role of mass in gravitational force; FE is proportional to charge, while FG is proportional to mass.

What is the Coulomb constant (k)?

The Coulomb constant is 8.99 × 10⁹ N m²/C², used in calculations of electric force.

What is the difference between electric and gravitational forces?

Electric forces can be attractive or repulsive, while gravitational forces are only attractive.

Why do we primarily notice gravity instead of electric forces in daily life?

Most atoms are electrically neutral, with equal numbers of protons and electrons, resulting in no net electric force.

How much stronger is the electric force compared to gravity?

The electric force is far stronger than gravity, by a factor of more than 10⁴⁰.

What is meant by charge being quantized?

Charge is quantized, meaning it comes in discrete amounts, such as the charge of a proton or electron.

What is the significance of the inverse square law in physics?

It describes how certain forces, like gravity and electric force, decrease with the square of the distance between objects.

What happens to gravitational force if the distance is tripled?

The gravitational force becomes one-ninth as strong.

What is the mass of a proton and an electron?

The mass of a proton is approximately 10⁻²⁷ kg, and the mass of an electron is about 10⁻³⁰ kg.

What is the effect of doubling the mass of an object on gravitational force?

Doubling the mass results in doubling the gravitational force experienced.

What is the effect of doubling the distance on electric force according to Coulomb's Law?

Doubling the distance results in one-fourth the electric force.

What does the term 'inverse square law' mean?

It refers to a relationship where a quantity is inversely proportional to the square of the distance from a source.

Why is gravitational force between everyday objects negligible?

The masses of everyday objects are too small relative to the gravitational constant, resulting in an insignificant force.

What is the typical charge of most objects around us?

Most objects have equal numbers of protons and electrons, resulting in a total charge of zero.

Why does gravity dominate at large scales?

Gravity cannot be neutralized and gets stronger as mass accumulates, making it the dominant force for planets and stars.

What happens when cloth and a glass rod are rubbed together?

The glass rod gains a positive charge, while the cloth gains a negative charge by stealing electrons from the glass.

What principle explains the conservation of charge?

Charge is never created nor destroyed, only transferred; the total charge of the glass rod and cloth together remains zero.

What is a scalar field?

A scalar field assigns a numerical value to every point in space without direction, such as temperature in a room.

What is a vector field?

A vector field assigns a value with both magnitude and direction to every point in space, such as wind speed and direction.