Lecture on Gravity, Electromagnetism, and Planetary Science

This set of flashcards covers essential vocabulary and concepts related to gravity, electromagnetism, and planetary science as discussed in the lectures.

Scientific method

A powerful process to understand the world through falsification of hypotheses.

Force

An influence that changes the motion of an object, characterized by magnitude and direction.

Mass

The amount of matter in an object, indicating its inertia.

Weight

The force exerted by gravity on an object.

Newton's first law of motion (Law of Inertia)

An object stays at rest or in uniform motion unless acted upon by an external force.

Newton's second law of motion

The acceleration of an object is proportional to the net force acting on it and inversely proportional to its mass.

Newton's third law of motion (Action-Reaction)

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

Energy

The ability of a body or system to perform work, which is conserved.

Potential energy (PE)

Stored energy, often due to an object's elevated position.

Kinetic energy (KE)

The energy of motion, which can convert to potential energy and vice versa.

Momentum

The quantity of motion of a moving body, conserved in the absence of external torque.

Gravity

A fundamental force that is always attractive, following an inverse square law.

Electric charge

A physical property of matter causing it to experience a force in an electric field.

Electromagnetic force

One of the four fundamental forces responsible for chemistry and biology.

Electric current

The flow of electric charge.

Ohm’s Law

States that current is directly proportional to voltage and inversely proportional to resistance.

Direct Current (DC)

Electric current that flows in one direction.

Alternating Current (AC)

Electric current that changes direction periodically.

Wave-particle duality

Light exhibits both wave and particle properties.

Reflection

The return of light to the medium it left.

Refraction

The bending of light as it passes into a different medium.

Scattering

The deviation of light from a straight path due to particles.

Doppler shift

The change in frequency of light due to the motion of the source relative to an observer.

Thermal radiation

Electromagnetic radiation emitted due to an object's temperature.

Stefan-Boltzmann law

The total energy emitted by a black body is proportional to the fourth power of its temperature.

Wien’s Law

The wavelength of maximum emission is inversely proportional to the temperature.

Magnetic field

The area surrounding a magnet, characterized by effects on electric charges.