A Level Physics Paper 1: Mechanics

• Physics is the natural science that studies matter, its fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force.
• A Level Physics Paper 1 typically assesses core physics principles and concepts.

Mechanics

• Kinematics is the study of motion without considering its causes.
• Displacement is the distance and direction of an object's change in position from a reference point.
• Velocity is the rate of change of displacement with respect to time, a vector quantity.
• Acceleration is the rate of change of velocity with respect to time, also a vector quantity.
• Equations of motion (SUVAT equations) relate displacement (s), initial velocity (u), final velocity (v), acceleration (a), and time (t) for uniform acceleration.
• Projectile motion involves objects moving under the influence of gravity, following a parabolic path when air resistance is negligible.
• Newton's first law states that an object at rest stays at rest, and an object in motion stays in motion with the same speed and in the same direction unless acted upon by a net force.
• Newton's second law states that the force acting on an object is equal to the mass of the object multiplied by its acceleration (F = ma).
• Newton's third law states that for every action, there is an equal and opposite reaction.
• Momentum is the product of an object's mass and velocity (p = mv).
• Impulse is the change in momentum of an object, equal to the force applied multiplied by the time for which it is applied (Impulse = FΔt).
• The principle of conservation of momentum states that the total momentum of a closed system remains constant if no external forces act on it.
• Work is done when a force causes a displacement (W = Fd cosθ, where θ is the angle between the force and displacement).
• Energy is the capacity to do work.
• Kinetic energy (KE) is the energy an object possesses due to its motion (KE = 1/2 mv^2).
• Gravitational potential energy (GPE) is the energy an object possesses due to its position in a gravitational field (GPE = mgh, where h is the height).
• The principle of conservation of energy states that energy cannot be created or destroyed, only transformed from one form to another.
• Power is the rate at which work is done or energy is transferred (P = W/t).
• Efficiency is the ratio of useful energy output to total energy input.

Materials

• Density is mass per unit volume (ρ = m/V).
• Hooke's law states that the extension of a spring is directly proportional to the force applied, provided the limit of proportionality is not exceeded (F = kx, where k is the spring constant and x is the extension).
• The spring constant (k) is a measure of the stiffness of a spring.
• Stress is the force per unit area acting on a material (stress = F/A).
• Strain is the extension per unit length of a material (strain = ΔL/L).
• Young's modulus is the ratio of stress to strain in the elastic region of a material (E = stress/strain).
• The elastic limit is the point beyond which a material will not return to its original shape when the stress is removed.
• Plastic deformation is permanent deformation that occurs when a material is stressed beyond its elastic limit.
• Tensile strength is the maximum stress a material can withstand before breaking.

Waves

• Waves transfer energy without transferring matter.
• Transverse waves have oscillations perpendicular to the direction of energy transfer.
• Longitudinal waves have oscillations parallel to the direction of energy transfer.
• Displacement is the distance of a point on a wave from its equilibrium position.
• Amplitude is the maximum displacement of a point on a wave from its equilibrium position.
• Wavelength is the distance between two consecutive points on a wave that are in phase (e.g., crest to crest).
• Period is the time taken for one complete oscillation.
• Frequency is the number of complete oscillations per unit time (f = 1/T).
• Wave speed is the distance traveled by a wave per unit time (v = fλ).
• Phase difference is the fraction of a cycle by which one wave leads or lags another.
• Superposition is the phenomenon that occurs when two or more waves overlap, resulting in a new wave pattern.
• Constructive interference occurs when waves are in phase, resulting in an increased amplitude.
• Destructive interference occurs when waves are out of phase, resulting in a decreased amplitude.
• Stationary waves are formed when two waves traveling in opposite directions interfere, resulting in nodes (points of zero displacement) and antinodes (points of maximum displacement).
• Reflection is the change in direction of a wave at an interface between two different media.
• Refraction is the change in direction of a wave as it passes from one medium to another, due to a change in speed.
• Diffraction is the spreading of waves as they pass through an opening or around an obstacle.
• Huygens' principle states that every point on a wavefront can be considered as a source of secondary wavelets that spread out in all directions with a speed equal to the speed of propagation of the wave.
• Interference patterns are produced when waves from coherent sources overlap.
• Coherent sources emit waves with a constant phase difference.
• The double-slit experiment demonstrates the wave nature of light and produces an interference pattern.
• Diffraction gratings are used to produce sharp interference patterns and can be used to measure the wavelength of light.
• The Doppler effect is the change in frequency or wavelength of a wave in relation to an observer who is moving relative to the wave source.

Electricity

• Electric charge is a fundamental property of matter that can be positive or negative.
• Coulomb's law states that the force between two point charges is directly proportional to the product of the charges and inversely proportional to the square of the distance between them.
• Electric field is the region around a charged object where a force would be exerted on other charged objects.
• Electric potential is the work done per unit charge to bring a positive test charge from infinity to a point in an electric field.
• Electric current is the rate of flow of electric charge (I = ΔQ/Δt).
• Conventional current flows from positive to negative.
• Resistance is the opposition to the flow of electric current (R = V/I).
• Ohm's law states that the current through a conductor is directly proportional to the voltage across it, provided the temperature remains constant.
• Resistivity is a measure of a material's resistance to the flow of electric current (ρ = RA/L).
• Power is the rate at which electrical energy is converted into other forms of energy (P = VI = I^2R = V^2/R).
• Electromotive force (EMF) is the total energy supplied per unit charge by a source.
• Internal resistance is the resistance within a source of EMF.
• Kirchhoff's first law (junction rule) states that the sum of currents entering a junction is equal to the sum of currents leaving the junction.
• Kirchhoff's second law (loop rule) states that the sum of the potential differences around a closed loop in a circuit is zero.
• Potential dividers are circuits that divide a voltage into smaller voltages.

Quantum Physics

• Photoelectric effect is the emission of electrons from a metal surface when light is shone on it.
• Photons are packets of electromagnetic energy (E = hf, where h is Planck's constant and f is the frequency).
• Work function is the minimum energy required to remove an electron from the surface of a metal.
• The de Broglie wavelength is the wavelength associated with a moving particle (λ = h/p, where p is momentum).
• Wave-particle duality is the concept that all matter exhibits both wave-like and particle-like properties.
• Energy levels are discrete, quantized values of energy that an atom can possess.
• Electron volt (eV) is the energy gained by an electron when it moves through a potential difference of 1 volt.

Study of motion. Key concepts include displacement, velocity, and acceleration. Equations of motion (SUVAT) are used. Projectile motion under gravity create parabolic paths.