Physics All Knowledge (EVERYTHING)

Mass

The quantity of matter in a body and a measure of its inertia.

Weight

The gravitational force exerted on a body by the Earth or another celestial body.

Density

Mass per unit volume of a material.

Relative Density

The ratio of the density of a substance to the density of pure water.

Displacement

The distance moved in a specified direction from a fixed reference point.

Velocity

The rate of change of displacement with time.

Acceleration

The rate of change of velocity with time.

Vector Quantity

A physical quantity that has both magnitude and direction.

Scalar Quantity

A physical quantity that has magnitude only.

Newton's First Law of Motion

A body remains at rest or travels at a constant velocity unless acted upon by a net external force.

Newton's Second Law of Motion

The rate of change of momentum of a body is directly proportional to the applied force and takes place in the direction of the force.

Newton's Third Law of Motion

If body A exerts a force on body B, body B exerts an equal and opposite force on body A.

Linear Momentum

The product of a body's mass and its velocity.

Law of Conservation of Linear Momentum

The total linear momentum of a closed system remains constant if no external forces act on it.

Force

An influence that can change the state of rest, motion, or shape of a body.

Friction

A force that opposes relative motion between two surfaces in contact.

Moment of a Force

The turning effect of a force about a pivot, equal to the force multiplied by the perpendicular distance from the pivot.

Principle of Moments

For a body in equilibrium, the sum of the clockwise moments about any point equals the sum of the anticlockwise moments about that same point.

Center of Gravity

The single point through which the entire weight of a body appears to act.

Stable Equilibrium

A state where a small displacement raises the center of gravity, causing a restoring moment that returns the object to its original position.

Unstable Equilibrium

A state where a small displacement lowers the center of gravity, causing a moment that moves the object further from its original position.

Neutral Equilibrium

A state where a small displacement keeps the center of gravity at the same height, leaving the object at rest in its new position.

Hooke's Law

The extension of a spring is directly proportional to the applied load, provided the limit of proportionality is not exceeded.

Limit of Proportionality

The maximum load a spring can support before the extension ceases to be directly proportional to the load.

Work Done

The product of a force and the distance moved by its point of application in the direction of the force.

Joule

The work done when a force of one Newton moves its point of application through a distance of one meter in the direction of the force.

Kinetic Energy

The energy possessed by a body due to its motion.

Gravitational Potential Energy

The energy possessed by a body due to its position in a gravitational field.

Law of Conservation of Energy

Energy cannot be created or destroyed, but can only be transformed from one form to another.

Power

The rate at which work is done or the rate at which energy is converted.

Watt

A rate of working or converting energy of one joule per second.

Efficiency

The ratio of useful energy output to total energy input, often expressed as a percentage.

Density Formula

ρ = m / V (Density = Mass / Volume)

Relative Density Formula

Relative Density = Density of substance / Density of water

Speed Formula

v = d / t (Speed = Distance / Time)

Velocity Formula

v = s / t (Velocity = Displacement / Time)

Acceleration Formula

a = (v - u) / t (Acceleration = [Final Velocity - Initial Velocity] / Time)

Equation of Motion 1

v = u + at

Equation of Motion 2

s = ut + 0.5at^2

Equation of Motion 3

v^2 = u^2 + 2as

Linear Momentum Formula

p = mv (Momentum = Mass x Velocity)

Force and Acceleration (Newton 2)

F = ma (Force = Mass x Acceleration)

Force and Momentum Change

F = (mv - mu) / t (Force = Change in Momentum / Time)

Weight Formula

W = mg (Weight = Mass x Gravitational Acceleration)

Moment of a Force

T = F x d (Torque/Moment = Force x Perpendicular Distance)

Hooke's Law Formula

F = kx (Force = Spring Constant x Extension)

Pressure Formula

P = F / A (Pressure = Force / Area)

Liquid Pressure Formula

P = hρg (Pressure = Depth x Density x Gravitational Acceleration)

Work Done Formula

W = F x d (Work = Force x Distance in direction of force)

Kinetic Energy Formula

Ek = 0.5mv^2 (Kinetic Energy = 0.5 x Mass x Velocity squared)

Gravitational Potential Energy

Ep = mgh (Potential Energy = Mass x Gravitational Acceleration x Height)

Power Formula 1

P = W / t (Power = Work Done / Time)

Power Formula 2

P = E / t (Power = Energy Converted / Time)

Mechanical Efficiency

Efficiency = (Useful Energy Output / Total Energy Input) x 100%

Kinetic Theory of Matter

States that all matter is composed of particles in a continuous state of random motion.

Brownian Motion

The continuous, random, haphazard motion of microscopic particles suspended in a fluid, caused by collisions with fluid molecules.

Temperature

A measure of the degree of hotness or coldness of a body, or a measure of the average kinetic energy of its particles.

Fixed Points

Distinct, reproducible temperatures used to define a temperature scale, such as the ice point and the steam point.

Ice Point

The temperature of pure melting ice at standard atmospheric pressure, defined as 0 degrees Celsius.

Steam Point

The temperature of steam above pure boiling water at standard atmospheric pressure, defined as 100 degrees Celsius.

Clinical Thermometer

A specialized thermometer with a narrow range, a constriction in the bore, and a thin glass bulb used to measure human body temperature.

Boyle's Law

For a fixed mass of gas at constant temperature, the pressure is inversely proportional to its volume.

Charles's Law

For a fixed mass of gas at constant pressure, the volume is directly proportional to its absolute temperature.

Pressure Law

For a fixed mass of gas at constant volume, the pressure is directly proportional to its absolute temperature.

Absolute Zero

The temperature at which the particles of a gas have minimum kinetic energy, defined as 0 Kelvin or minus 273 degrees Celsius.

Heat Capacity

The quantity of thermal energy required to raise the temperature of a body by one Kelvin.

Specific Heat Capacity

The quantity of thermal energy required to raise the temperature of one kilogram of a substance by one Kelvin.

Latent Heat

The thermal energy absorbed or released during a change of phase at constant temperature.

Specific Latent Heat of Fusion

The quantity of thermal energy required to change one kilogram of a substance from solid to liquid without a change in temperature.

Specific Latent Heat of Vaporization

The quantity of thermal energy required to change one kilogram of a substance from liquid to gas without a change in temperature.

Conduction

The transfer of thermal energy through a material by molecular vibrations and free electron movement, without bulk movement of the material.

Convection

The transfer of thermal energy through a fluid by the actual bulk movement of the fluid itself, caused by changes in density.

Radiation

The transfer of thermal energy by means of electromagnetic waves, which does not require a material medium.

Good Emitters and Absorbers

Matt, black surfaces which absorb and radiate thermal energy highly efficiently.

Good Reflectors

Shiny, silver surfaces which reflect thermal radiation efficiently and are poor emitters and absorbers.

Greenhouse Effect

The process where atmospheric gases trap long-wavelength infrared radiation emitted by the Earth, warming the planet.

Celsius to Kelvin Conversion

T = θ + 273.15 (Kelvin Temperature = Celsius Temperature + 273.15)

General Heat Equation

ΔE = mcΔθ (Thermal Energy = Mass x Specific Heat Capacity x Change in Temperature)

Heat Capacity Formula

C = mc or C = ΔE / Δθ (Heat Capacity = Mass x Specific Heat Capacity)

Latent Heat Formula

ΔE = mL (Thermal Energy = Mass x Specific Latent Heat)

Boyle's Law Equation

P1 x V1 = P2 x V2 (At constant temperature)

Charles's Law Equation

V1 / T1 = V2 / T2 (At constant pressure, T in Kelvin)

Pressure Law Equation

P1 / T1 = P2 / T2 (At constant volume, T in Kelvin)

General Gas Law Equation

(P1 x V1) / T1 = (P2 x V2) / T2 (T must be in Kelvin)

Wave

A disturbance that transfers energy from one point to another without transferring matter.

Transverse Wave

A wave in which the particles of the medium oscillate perpendicular to the direction of wave propagation.

Longitudinal Wave

A wave in which the particles of the medium oscillate parallel to the direction of wave propagation.

Wavefront

A line or surface connecting adjacent particles that are in phase, such as all crests.

Amplitude

The maximum displacement of a particle in a wave from its undisturbed or rest position.

Wavelength

The distance between two consecutive points in phase on a wave, such as from crest to crest.

Frequency

The number of complete wave cycles produced or passing a point per second.

Period

The time taken for one complete wave cycle to pass a point.

Laws of Reflection

State that the incident ray, reflected ray, and normal all lie in the same plane, and the angle of incidence equals the angle of reflection.

Refraction

The change in direction of a wave as it crosses a boundary between two media of different optical densities, caused by a change in wave speed.

Laws of Refraction

State that the incident ray, refracted ray, and normal all lie in the same plane, and Snell's law applies.

Snell's Law

For light traveling between two given media, the ratio of the sine of the angle of incidence to the sine of the angle of refraction is a constant.

Refractive Index

The ratio of the speed of light in a vacuum to the speed of light in a medium.

Critical Angle

The angle of incidence in the optically denser medium for which the angle of refraction in the less dense medium is 90 degrees.

Total Internal Reflection

The complete reflection of a light ray back inside an optically denser medium when the angle of incidence exceeds the critical angle.

Diffraction

The spreading of waves as they pass through a narrow gap or around the edge of an obstacle.