Notes, summaries, assignments, exams, and problems for Physics

Fundamental Forces in Physics

Weight (W)

• Weight is the gravitational force that exists between masses. Specifically, it is the force exerted on an object by a planet's gravity when the object is at the planet's surface.
• It can be calculated using the formula: W = mg
  • Where: m is the mass of the object under study, measured in kilograms (kg) in the SI unit system.
  • g is the acceleration due to gravity at the planet's surface. On Earth, g ≈ 9.81 m/s².
• Weight is directed along the line connecting the object under study with the planet's center, oriented towards the planet's center.

Normal Force (N)

• The Normal Force is a contact force that acts between two surfaces that are touching each other.
• It is often calculated indirectly, as it balances other forces

Simple Harmonic Motion and Waves

Vibrations and Frequency

At the equilibrium position of a mass attached to a spring, the velocity reaches a maximum.

Frequency is the number of cycles or vibrations per unit of time for a system in simple harmonic motion.

Sound and Pitch

The perceived highness or lowness of a sound is known as pitch.

The Doppler Effect

The Doppler Effect applies to all types of waves.

Electromagnetic Spectrum and Television

Radio waves are the portion of the electromagnetic spectrum utilized in television technology.

Electromagnetic Radiation in a Vacuum

In a vacuum, electromagnetic radiation of short wavelengths travels at the same speed as radiation of long wavelengths.

Mirrors and Refraction

Image Formation by a Flat Mirror

A flat mirror

Formulas to Calculate Pressure

P=pgh P=F/A Pabs=Pgauge+Patm P=Pa p=kg/m3 g=m/s2 h=m

Newtons and Pascal

P=Pa Pa=N/m2 Pa in 1 atm 101,325Pa

Archimedes Principle of Buoyancy

An object submerged in any fluid will experience a buoyant force equal to the weight of the fluid it has displaced.

Pressure

Air pressure in the wheels of the car, buoyancy: (the force that makes objects float) the boat floats because the fluid is denser than the object.

Buoyancy

Fw =m*g p=m/v Fb=Fa+Fw

Waves

Regards to medium mechanical waves (need a medium), electromagnetic (can propagate in a vacuum), regards to propagation longitudinal (parallel to the direction of the propagation), transverse (perpendicular), circular (waves on water, circular fashion).

Classify Sounds Waves

Lower... Continue reading "Physics Formulas and Concepts for Pressure, Waves, and Electricity" »

Why Knowledge of Perrault's Tales Matters for Understanding Carter's Rewritings

Understanding Charles Perrault's original fairy tales, such as "Bluebeard" and "Cinderella," is crucial for interpreting Angela Carter's reimagined versions. Carter builds upon Perrault's narratives, introducing feminist perspectives and challenging traditional tropes.

Cinderella

In Perrault's "Cinderella," the father's role in his daughter's mistreatment is notably absent. Maria Tatar argues that Perrault, writing for an affluent audience, avoids placing blame on male figures. Carter, however, metafictionally highlights the father as the "unmoved mover," dismantling the stereotypical image of the wicked stepmother and exposing the patriarchal structures within the... Continue reading "Feminist Retellings: Deconstructing Perrault's Fairy Tales in Angela Carter's Works" »

Compact Objects: An Overview

White Dwarfs

Chandrasekhar Limit: The maximum mass of a white dwarf, about 1.4 solar masses. A white dwarf of greater mass cannot support itself and will collapse.

Roche Lobe: The volume of space a star controls gravitationally within a binary system.

Neutron Stars

Angular Momentum: A measure of the tendency of a rotating body to continue rotating. Mathematically, the product of mass, velocity, and radius.

Accretion Disk: The rotating disk that forms in some situations as matter is drawn gravitationally toward a central body.

Type I Supernova: A supernova explosion caused by the collapse of a white dwarf.

Type II Supernova: A supernova explosion caused by the collapse of a massive star.

Synchrotron Radiation: Radiation emitted... Continue reading "Compact Objects: White Dwarfs, Neutron Stars, and Black Holes" »

1. What is Electric Charge?

Electric Charge is a fundamental property that all objects possess.

2. True or False: Atomic Structure and Current

• a. The atom is comprised of bigger particles.
  FALSE. The atom is comprised of smaller particles.
• b. Protons have a negative charge.
  FALSE. Protons have a positive charge.
• c. Neutrons have a positive charge.
  FALSE. Neutrons do not have an electric charge.
• d. An electric current is a continuous movement of electrons from the positive pole to the negative pole.
  FALSE. An electric current is a continuous movement of electrons from the negative pole to the positive pole.

3. Why is Matter Neutral?

Matter is neutral because it does not have a net electric charge; the number of electrons is equal to the number of protons.... Continue reading "Fundamentals of Electric Charge and Circuits" »

Chapter 6

1) How and why were the Nestors modified?

The Nestors were modified by not having the complete First Law of Robotics impressioned in them. It was modified so that the Nestors wouldn't try to save men who were working with radiation.

2) Why was the Nestor 10 lost?

Nestor 10 was lost because General Black told the robot to 'get lost.'

3) The scientist did three tests. Why are these things important?

a) Cubicles

The robots sat in the cubicles during the testing. They could not see each other, only the human in the middle of the Radiation room.

b) Heat radiation

Heat radiation was used during the last test and is harmless to robots.

c) Gamma radiation

Gamma radiation destroys robots, but small amounts are harmless to humans.

4) Did the tests succeed,

Fundamental Physics Definitions

Properties of Matter and Energy

Electrical Charge

Property of matter related to the proportion existing between protons and electrons.

Energy

Capacity bodies have to produce changes in themselves and in other bodies.

Types of Energy

• Kinetic Energy (E_k): Possessed by bodies in motion: E_k = 1/2 * m * v²
• Potential Energy (E_p): Possessed by bodies due to the position they occupy in space or the deformation they are experiencing. E_p = m * g * h
• Gravitational Potential Energy: The energy of a body at a certain height above the surface.
• Elastic Potential Energy: Energy of an elastic body when it is deformed.
• Mechanical Energy: Possessed by bodies due to the velocity they have and their position in space.
• Electrical Energy: Produced