Physics Paper 1

• What does the term "energy" represent in physics?

  It indicates potential interactions in a system
• How is energy measured?

  In Joules
• What is the principle of conservation of energy?

  Energy cannot be created or destroyed
• What is the equation for kinetic energy?

  $E =$$\frac{1}{2} mv^2$
• What does gravitational potential energy depend on?

  Mass, height, and gravitational field strength
• What is the formula for gravitational potential energy?

  $E =$$mgh$
• What does the specific heat capacity (shc) measure?

  Energy needed to raise 1 kg by 1°C
• What is the equation for change in thermal energy?

  $E =$$mc\Delta T$
• What happens to particles when thermal energy increases?

  They move faster
• What is chemical potential energy?

  Energy stored in food or fuels
• What is required for energy transfer in a system?

  Energy must move between objects or stores
• What is a closed system?

  No energy is lost or gained from surroundings
• How does gravitational potential energy convert to kinetic energy in a roller coaster?

  GPE decreases while KE increases as it falls
• How can you find the speed of an object using energy equations?

  Rearrange kinetic energy equation for speed
• What is the equation for power?

  $P =$$\frac{E}{t}$
• What does efficiency measure?

  Useful energy output to total energy input
• How do you calculate efficiency as a percentage?

  Multiply the decimal by 100
• What happens to energy in poorly insulated buildings?

  Heat is lost through walls and windows
• What are finite energy sources?

  Sources that cannot be replenished
• What is electricity?

  Flow of charge, typically electrons
• What is required for a circuit to function?

  A complete loop of components and wires
• What does potential difference (PD) measure?

  Energy transferred per coulomb of charge
• How is potential difference measured?

  With a voltmeter connected in parallel
• What is the equation for potential difference?

  <latex{V = \frac{E}{Q}}</latex>
• What does current measure in a circuit?

  Rate of flow of charge
• What is the equation for current?

  <latex{I = \frac{Q}{t}}</latex>
• What is resistance in a circuit?

  Opposition to the flow of current
• How does resistance affect current in a circuit?

  Higher resistance results in lower current
• What is Ohm's Law?

  <latex{V = IR}}</latex>
• What does a straight line on an IV graph indicate?

  Constant resistance in the component
• How does a bulb's IV graph differ from a resistor's?

  A bulb's graph is curved, indicating changing resistance
• What is the relationship between PD and current in a resistor?

  They are directly proportional.
• What does a straight line graph of PD and current indicate?

  It shows constant resistance in a resistor.
• What happens to the graph if the battery is reversed?

  Negative values for both, still straight line.
• What does the gradient of the line in a V-I graph represent?

  It shows the resistance of the resistor.
• What is the equation for resistance according to Ohm's law?

  V = I × R
• How can you find the resistance from an IV graph?

  Use R = V / I at any point.
• What happens to the graph when using a bulb instead of a resistor?

  The graph becomes curved, indicating changing resistance.
• Why does the resistance of a metal filament change with increased PD and current?

  Increased collisions with vibrating ions raise resistance.
• What is the behavior of a thermistor with temperature changes?

  Its resistance decreases as temperature increases.