physics paper 1

• state the role of step up and step down transformers

  step up transformers increase the potential difference so less energy is lost in the transmission cables. the step down transformers reduce potential difference to make it safe before the electricity is passed to homes
• specific latent hear of fusion

  the energy required to change 1 kg of a substance from a solid to liquid with no change in temperature
• specific latent heat of vaporisation

  the energy required to change one kg of a substance from a liquid to a gas with no change in temperature
• Work Formula

  W = F × d
• Resistor Formula

  V = I × R
• Series Circuit Current

  Current remains the same throughout the circuit, total resistance is the sum of individual resistances
• Parallel Circuit

  Total resistance decreases, same current and voltage for each resistor
• Ohm's Law

  I = V / R
• Power Formula

  P = VI
• Power and Energy Relationship

  P = E / t
• Alpha Radiation

  High-energy, positively charged particles, emitted by certain radioactive isotopes
• Alpha Particle Interactions

  Direct ionization, Coulomb scattering, Nuclear reactions
• V = IR

  Voltage as a function of current and resistance
• V = ΔV / Δt

  Voltage as a function of change in voltage and time
• V = R * I


  Voltage as a function of resistance and current
• specific latent heat

  energy= mass x specific latent heat
• particle motion of gases


  pressure of gasses is due to the particles colliding with the walls of the container that the gas is filled in. by colliding with the walls of the container the gas particles exert a pressure. high temperature=high kinetic energy=high pressure
• internal energy

  all particles have kinetic and potential energy. (intermolecular forces and chemical bonds) internal energy refers to the energy stored in a system by the particles, total kinetic and potential energies of all atoms and molecules that make up a system
• alpha scattering- results

  told scientists atoms is mainly empty space

  centre of atoms must have a positive charge
• Kinetic Energy Equation


  (1/2)mv^2