Physics DYNAMICS

• What is a vector in physics?

  A measurement that requires direction to be fully described
• What are the five vectors you need to be aware of at National 5 physics?

  • Displacement
  • Velocity
  • Acceleration
  • Force
  • Weight
• How are scalars defined in National 5 physics?

  Quantities that can be fully described by a single number
• Which of the following is a vector: speed, weight, or energy?

  Weight
• What is the formula for average speed?

  Average speed = total distance / total time
• How do you calculate instantaneous speed at the bottom of the slope?

  By using the formula \( \frac{L}{T2} \)
• What does Newton's third law state regarding forces?

  Every action has an equal and opposite reaction
• How do you calculate the minimum power rating of a motor lifting a mass?

  Using the formula \( P = \frac{E}{T} \)
• What is the gravitational potential energy gained when lifting a mass?

  It is calculated using \( E_p = mgh \)
• How do you convert 2 minutes into seconds?

  By multiplying by 60 to get 120 seconds
• What happens to the weight of a satellite in orbit?

  It is still affected by Earth's gravitational field
• Why does a satellite appear weightless while orbiting the Earth?

  Because it is in freefall
• How do you calculate the distance from the Earth to the Moon using light travel time?

  By using \( \text{Distance} = \text{Speed} \times \text{Time} \)
• What is the altitude of a satellite related to its orbital period?

  The lower the altitude, the shorter the period
• What is the approximate age of the universe?

  13.8 billion years
• What does the Big Bang Theory describe?

  The origin of the universe
• What happens to the resistance of an LDR as light levels decrease?

  The resistance increases
• How do you calculate the charge passing through a circuit?

  Using \( Q = I \times T \)
• What is the relationship between power, voltage, and current?

  Power \( P = V \times I \)
• How do you find the total resistance in a parallel circuit?

  Using \( \frac{1}{R_{total}} = \frac{1}{R_1} + \frac{1}{R_2} + \frac{1}{R_3} \)
• What are the key characteristics of a voltage divider circuit?

  • Voltage is shared between resistors
  • The ratio of voltages equals the ratio of resistances
  • Total voltage is equal to the sum of voltages across each resistor
• What happens to the current in a circuit when the resistance of an LDR increases?

  The current decreases
• How does the resistance of resistors in parallel affect the total resistance?

  The total resistance decreases
• What is the formula for calculating power in terms of energy and time?

  Power \( P = \frac{E}{T} \)
• How do you convert kilowatts to watts?

  By multiplying by 1,000
• What is the significance of a fuse in an electrical circuit?

  It protects the circuit from excessive current
• What is the effect of increasing the resistance in a circuit on the current flow?

  The current flow decreases
• What is the unit of charge?

  Coulomb (C)
• What does an LDR do in a circuit?

  It changes resistance based on light levels
• How do you calculate the total resistance in a series circuit?

  By adding the resistances together
• What is the relationship between current, voltage, and resistance in a circuit?

  Ohm's Law: \( V = I \times R \)
• What is the formula for calculating energy in terms of power and time?

  Energy \( E = P \times T \)
• What is the purpose of a voltmeter in a circuit?

  To measure the voltage across components
• How do you determine the total current in a parallel circuit?

  By adding the currents through each branch
• What happens to the total current in a circuit when more resistors are added in parallel?

  The total current increases
• What is the unit of power?

  Watt (W)
• What is the effect of increasing voltage in a circuit with constant resistance?

  The current increases
• How do you calculate the total voltage in a series circuit?

  By adding the voltages across each component
• What is the impact of resistance on the flow of current in a circuit?

  Higher resistance reduces current flow
• What is the formula for calculating total resistance in series?

  Total resistance \( R_{total} = R_1 + R_2 + R_3 \)