Science Physics

• the dangers associated with mains electricity

  shocks and burns
• Describe current

  the rate of flow of charge
• Explain why current will only flow through a complete circuit. 

   number of electrons flowing from voltage source to the circuit should be equal to number of electrons flowing from circuit to the voltage source
• what is a variable resistor

  a resistor of which you can change the resistance
• what does a circuit cell do?

  produce potential difference
• a battery is?


  a cell but better
• what does a switch do ?

  A switch turns things on/off
• what does a voltmetre do?


  Measures voltage
• what does an ammetre do?

  Measures current(amps)
• what does a resistor do?

  Opposes or limits the flow of electric current.
• what does a motor do?

  Generate movement
• what is a series circuit?

  A circuit where the components are connected in a single path, so the current flows through each component in sequence.
• what is meant by the term ‘electrical conductor’

  a substance that allows electricity to flow through it.
• what is meant by the term ‘electrical insulator’


  material where electrical current doesn't flow freely
• metals that conduct electricity?

  nickel, cobalt, iron
• electrical conductivity relates to the number of?

  Free electrons
• current is measured using an ammeter and has the unit?

  amps
• to measure the current flowing through a component in a circuit, the ammeter must be?

  connected in series with it
• Is current is the same throughout a series circuit?

  Yes
• effect of changing the components in a series circuit has on the current?

  more resistors = harder it is for current to flow
• what is a parallel circuit?

  A circuit with multiple paths for current to flow.
• what is resistance?


  reduction in the flow of charge in a circuit and has the unit Ohms. 
• True or False? greater the resistance, the higher the current

  False, it's the greater the resistance, the lower the current
• all components provide resistance in a circuit and that increasing the number of components what the current?

  Decreases
• What is the energy carried by the electrons between two points in a circuit?

  potential difference
• potential difference

  is shared between components in a series circuit and that the potential difference is the same across components connected in parallel.
• calculate resistance for a component using the current and potential 


  calculate the resistance using R = V/I.
• what is T


  time(seconds)
• what is I


  current (amps)
• whats is V


  voltage (volts)
• whats is Q


  charge (Coulombs)
• equation to slove for I?

  I = Q/T
• Solve for R


  V = I/R (R=VI)
• A circuit is set up to test two different resistors. Resistor 1 has a resistance of 4 ohms and Resistor 2 has a resistance of 2 ohms. Which resistor will have the bigger current flowing through it, if the potential difference is constant?

  resistor 2
• Voltage is another name for the __________ difference. What word completes the sentence?

  potential
• equation for V

  V=E/Q E=energy
• For a given potential difference, a bigger resistance means a smaller __________ through a component. What one word completes this sentence?

  current