Comprehensive Physics: Orbits, Transformers, Electromagnetic Waves, and Atomic Models

What is orbital motion?

An example of uniform circular motion where centrifugal force is provided by gravitational force.

What is the altitude range for Low Earth Orbit (LEO)?

Altitude of 2000 km with a radius of 8500 km.

What is the orbital period and velocity of satellites in Low Earth Orbit?

Orbital period of 1-2 hours and velocity of 8 km/s.

What are the primary uses of Low Earth Orbit satellites?

Surveillance, monitoring, and some communications.

What is the altitude range for Medium Earth Orbit (MEO)?

Altitudes of 2000-36000 km.

What are the primary uses of Medium Earth Orbit satellites?

Navigation and communication.

What is the altitude and orbital period of Geostationary Orbit satellites?

Altitude of 36,000 km and an orbital period of 24 hours.

What is the velocity of satellites in Geostationary Orbit?

Velocity of 3 km/s.

What are the primary uses of Geostationary Orbit satellites?

Communications and broadcasting.

What is the function of a transformer?

Devices that allow the voltage of an electrical signal to increase (step up) or decrease (step down).

What are the two main components of a transformer?

Primary winding/coil (input) and secondary winding/coil (output).

What type of current must transformers use?

Alternating current.

What causes copper loss in transformers?

Resistance in the coils/wiring produces heat when current flows through them.

What is Lenz's Law?

States that the direction of an induced current opposes the change in magnetic flux that caused it.

What does Faraday's Law describe?

How a changing magnetic field induces an electromotive force (EMF) in a conductor.

What is back electromotive force (back EMF)?

The voltage that opposes the change in current which induced it.

What are the two main components of a simple motor?

Stator (produces magnetic force) and rotor (where current flows in a magnetic field).

What is an AC generator?

A device that converts energy into electrical energy using Faraday's law of induction.

What is the significance of James Maxwell's work?

He unified electricity and magnetism and predicted the speed of electromagnetic waves.

What is required to produce an electromagnetic wave?

An oscillating charged particle to create a changing electric and magnetic field.

What was Galileo's method for measuring the speed of light?

Using a stopwatch and lamps on mountains, but it was very inaccurate.

How did Romer measure the speed of light?

By timing the orbits of Jupiter's moons, achieving greater accuracy.

What was Fizeau's method for measuring the speed of light?

Using a rotating cogwheel to block returning light at the right speed.

What is the particle theory of light proposed by Newton?

Light is made of tiny corpuscles that explain reflection and refraction but fail to explain interference and polarization.

What is Huygens' wave theory of light?

Light behaves as a wave spreading through an ether, explaining reflection, refraction, and diffraction.

What is the quantum model of light proposed by Einstein?

Light consists of small, discrete energy packets called photons, emitted or absorbed in full.

What is the photoelectric effect?

The emission of electrons from a metal surface when light shines on it, with key observations that wave theory couldn't explain.

What happens to spectral lines at higher gas density or pressure?

They broaden and can shift slightly in wavelength due to more collisions between particles.

What is the Doppler shift?

The change in wavelength of light from a star or planet moving toward or away from Earth.

What are Einstein's two postulates of relativity?

The speed of light is absolute in all reference frames, and all inertial frames of reference are equivalent.

What is the Big Bang theory?

The theory that the universe began nearly 14 billion years ago as pure radiation that expanded and cooled to form matter.

What is the inflation period in cosmology?

A phase where the universe expanded rapidly, creating a cycle of faster occurrences.

What phenomenon occurs when matter and antimatter combine?

Annihilation, which produces energy.

What did Hubble discover about the universe?

The universe is expanding, evidenced by redshift in distant galaxies.

What is Hubble's Law?

The relationship that shows galaxies moving away from Earth exhibit redshift, correlating with their distance.

What is nuclear fusion?

The process where light atomic nuclei combine to form a heavier nucleus, releasing energy.

What is the Proton-Proton (pp) Chain?

A fusion process in small stars like the Sun, where hydrogen nuclei fuse to form helium.

What is the CNO Cycle?

A fusion process in massive stars using carbon, nitrogen, and oxygen as catalysts to convert hydrogen into helium.

What is the Triple-Alpha Process?

A fusion process in red giants where helium fuses into carbon once hydrogen is depleted.

What does the uncertainty principle state?

It is impossible to know both the exact position and momentum of a particle simultaneously.

What did the Maltese Cross Experiment demonstrate?

Cathode rays travel in straight lines and can be blocked by solid objects.

What was concluded from the Paddle Wheel Experiment?

Cathode rays have mass and kinetic energy, indicating they are particles.

What did JJ Thomson discover using the Cathode Ray Tube?

He discovered the electron and measured its charge-to-mass ratio.

What was the outcome of the Oil Drop Experiment by Robert Millikan?

He determined the charge of a single electron and calculated its mass.

What are the characteristics of Alpha (α) Radiation?

Consists of 2 protons and 2 neutrons, has a +2 charge, low penetration, and is deflected toward a negative plate.

What are the characteristics of Beta (β) Radiation?

Consists of high-speed electrons, has a -1 charge, medium penetration, and is deflected toward a positive plate.

What are the characteristics of Gamma (γ) Radiation?

High-energy electromagnetic waves, neutral charge, very high penetration, and not deflected in fields.

What did the Geiger-Marsden Experiment reveal about the atom?

The atom is mostly empty space with a small, dense nucleus containing positive charge and mass.

What did James Chadwick discover?

The neutron, a neutral particle in the nucleus, explaining why atomic mass is greater than the number of protons.

What does the Bohr Model propose about electrons?

Electrons orbit the nucleus in fixed energy levels and can jump between levels by absorbing or emitting energy.

What are de Broglie Waves?

The idea that all matter has wave-like properties, linking quantum mechanics and classical physics.

What is nuclear fission?

The splitting of a heavy nucleus into two smaller nuclei, releasing energy, neutrons, and radiation.

What is the Standard Model of Matter?

A theory describing the fundamental particles (fermions and bosons) and their interactions, excluding gravity.

What are fermions?

Building blocks of matter with half-integer spin, including quarks and leptons.

What are bosons?

Force carriers with integer spin, mediating forces between fermions.

What is the Large Hadron Collider (LHC)?

The world's largest particle accelerator, used to collide high-energy protons to study fundamental particles.

What significant discovery was made at the LHC in 2012?

The discovery of the Higgs boson, confirming predictions of the Standard Model.