Physics 1

• What is the radius of the nucleus?

  1/10000th of the radius of the atom
• How must an ammeter be connected?

  In series.
• Where does all energy end up ultimately?

  Dissipated to the surroundings
• How must a voltmeter be connected?

  In parallel.
• Describe the plum pudding model of the atom

  Ball of positive charge with negative electrons embedded in it
• Give the mass, charge and position for a proton

  • mass = 1
  • charge = positive
  • Position = nucleus
• Give the mass, charge and position for a neutron

  • Mass = 1
  • charge = 0
  • Position = nucleus
• Give the mass, charge and position for the electron

  • Mass = very small
  • Charge = negative
  • position = orbits
• What is the name of the current model of the atom?

  Nuclear model
• How does the resistance of a thermistor change of temperature?

  as temperature increases, the resistance decreases
• Describe the alpha particle scattering experiment

  Alpha particles are fired as thin gold leaf. Particles scattered and bounced back indicating that there was a small positive nucleus, but mostly empty space
• Name two types of transformers and what they do

  • Step up = increases voltage, decreases current
  • step down = decreases voltage, increases current
• Describe a beta particle

  A single fast moving electron
• equation for elastic potential energy: Ee = 1/2 x spring constant x extension squared
• Define half-life

  The time taken for the number of nuclei of the isotope in a sample to halve, or the time taken for the count rate of a sample to fall to half its initial level
• What is the radius of an atom?

  1 x 10^-10
• What can we assume for a parallel circuit?

  The current is shared between branches, voltage is the same on each branch
• Define specific latent heat

  The energy needed for 1 kg of a substance to change state with no change in temperature
• What happens to the atomic number and mass number in alpha decay?

  Atomic number decreases by two, mass number decreases by four
• Define national grid


  System of cables and transformers linking power stations to consumers
• Describe an alpha particle

  A helium nucleus, (2 protons, 2 neutrons)
• What happens to atomic number and mass number in beta decay?


  Atomic number increases by 1, mass number stays the same.
• What is radioactive decay?

  A random process where a nucleus gives out radiation and changes to become more stable
• How does an earth wire prevent electrocution?

  Allows a large current flow to earth, then the fuse blows
• State the colours and functions of a 3 wires in a 3 core cable

  • blue = neutral
  • brown = live
  • yellow/green = Earth
• How does the resistance of an LDR change with light?

  As light intensity increases, LDR resistance decreases
• What can we assume for a series circuit?

  The current is the same all way round, voltage is shared between components
• Give the fourth type of nuclear radiation

  a neutron
• Describe a gamma ray

  A high frequency, short wave length EM wave
• State the properties of the UK mains AC supply

  230 volts, 50 hertz
• When referring to energy changes, what is meant by a system?

  An objects or group of objects
• efficiency = useful energy/total energy transferred
• What two types of energy make up internal energy?

  Kinetic and potential
• Name the physical changes of state


  Melting, boiling, sublimation, condensation, freezing
• By what method is heat energy transferred in a solid?

  Conduction
• define power


  rate at which energy is transferred