All Of IGCSE Physics Formulas (All Calculations & Tips)

Motion and Graphs

  • Speed and Motion Graphs

    • Speed Increases: Graph shows a positive slope.

    • Speed Decreases: Graph shows a negative slope.

    • Speed Constant: Graph is a horizontal line.

    • Speed Stationary: Graph is a flat line at zero.

Speed-Time Graphs

  • Acceleration Increasing: Graph slopes upward.

  • Acceleration Decreasing: Graph slopes upward at a decreasing rate.

  • Deceleration Decreasing: Graph slopes downward at a decreasing rate.

  • Deceleration Increasing: Graph slopes downward steeply.

  • Key Calculations:

    • Speed: Gradient of the distance-time graph.

    • Distance: Speed × Time.

    • Distance from Velocity-Time Graph: Area under the graph.

Terminal Velocity

  • Speed initially increases with air resistance.

  • At terminal velocity: Weight = Air Resistance.

Momentum

  • Momentum Formula: Momentum = Mass × Velocity.

  • Can be positive or negative depending on direction.

  • Equilibrium: Anti-clockwise force = Clockwise force.

  • Principle of Momentum: Total momentum before collision = Total momentum after collision.

Impulse

  • Impulse = Change in Momentum.

  • Formula: Impulse = Force × Time (measured in Newton-seconds).

  • Force: Mass × Acceleration.

Pressure in Liquids

  • Pressure increases with depth.

  • Pressure Formula in Fluids: Pressure = Density × Gravity × Height.

  • Molecules exert pressure by colliding with walls.

  • Change in Momentum: ( \Delta P = MV - \mu / t ) affects pressure.

Boyle's Law

  • Formula: P1V1 = P2V2.

  • Decreasing volume leads to increased pressure due to more collisions.

  • Pressure also increases with temperature due to faster molecular motion.

Waves

  • Refraction: Bending of waves when moving from deep to shallow medium.

  • Wave Equation: Speed = Frequency × Wavelength.

  • Diffraction and Reflection:

    • Waves diffract when approaching barriers.

    • Larger barriers cause reflection.

Thermal Physics

  • Boiling vs. Evaporation:

    • Boiling: Fixed temperature and constant; happens throughout the liquid.

    • Evaporation: Happens at any temperature on the surface; causes cooling.

Properties of a Thermometer

  • Range: Difference between max and min temperatures.

  • Linearity: Rate of expansion.

  • Responsiveness: Reaction to temperature changes.

  • Sensitivity: Change of length per degree.

Heat Transfer

  • Methods: Conduction, Convection, Radiation.

Light

  • Law of Reflection: Angle of incidence = Angle of reflection.

  • Image Characteristics: Virtual, upright, same size.

  • Refraction: Bending of light through different densities.

  • Dispersion: Spreading results in ROYGBIV spectrum.

  • Total Internal Reflection: Occurs when angle of incidence > critical angle.

Magnetism

  • Magnetic Force: Force produced by a magnetic field.

  • Magnetism Types: Waves, stroking, hammering, demagnetizing.

Resistance Factors

  • Affected by material, length, temperature, and cross-sectional area.

  • Ohm's Law: V = IR.

  • Electromagnetism: Magnetic field from passing current.

Transformers

  • Focus on the turns ratio.

Atomic Physics

  • Structure of an Element: Chemical symbol, nuclear number, proton number.

  • Nuclear Reactions:

    • Fission: Nucleus splits.

    • Fusion: Nucleus joins.

Nuclear Radiation

  • Types: Alpha (Helium, mass 4), Beta (high energy), Gamma (electromagnetic radiation).

  • Penetration Ability: Ranges from low (alpha) to high (gamma).

Radioisotopes

  • Uses include medical applications and smoke detectors.

  • Safety Precautions: Use adequate containers to prevent radiation exposure.