I-V characteristics

• Who is demonstrating the physics practical in the study material?

  1. Roots
• What is the purpose of the practical being demonstrated?

  To find the IV characteristics of components
• What type of resistor is being tested in the practical?

  100 ohm resistor
• What other components are mentioned in the practical?

  Filament lamp and diode
• Why is a variable resistor needed in the experiment?

  To adjust resistance for accurate readings
• What is the maximum resistance of the variable resistor used?

  1 kilo ohm
• What happens if the variable resistor's resistance is too small?

  It won't yield good results
• What power supply voltage is mentioned for the experiment?

  Up to 5 volts
• What is the role of the ammeter in the circuit?

  To measure the current flowing through
• What reading did the ammeter show initially?

  -0.06 amps
• What should be done if the ammeter shows a negative reading?

  Swap the leads around
• What is the voltmeter's role in the circuit?

  To measure the potential difference
• How should the voltmeter be connected in the circuit?

  Across the component being tested
• What is the first current reading taken in the experiment?

  0.01 amps
• What is the corresponding voltage reading at 0.01 amps?

  1 volt
• What is the maximum current reading taken in the experiment?

  0.05 amps
• What happens when the direction of current is reversed?

  Current and voltage readings become negative
• What is the voltage reading at -0.01 amps?

  -1.0 volts
• What is the shape of the graph for a resistor?

  A straight line
• What does Ohm's law state?

  Voltage equals current times resistance
• What indicates that a resistor is an ohmic conductor?

  Constant resistance across varying current
• What is the behavior of a filament lamp in the experiment?

  It shows non-linear resistance
• What is the maximum PD across the filament lamp at 0.05 amps?

  3.5 volts
• Why does the resistance of the filament lamp increase with current?

  It gets hotter, causing more collisions
• What is the minimum voltage needed for the diode experiment?

  0.55 volts
• What happens to the current when the voltage across the diode is negative?

  Current is zero
• What does the graph of a diode look like?

  Current increases sharply after a threshold
• What is a key characteristic of diodes?

  They allow current to flow in one direction
• How does the resistance of a diode change with voltage?

  Resistance decreases sharply after a threshold
• What is the aim of the investigation described?

  To investigate I-V characteristics of circuit elements
• What types of circuit elements are investigated in the study?

  Filament lamp, diode, and resistor
• How does the resistance of resistors behave as voltage increases?

  Resistance does not change with voltage
• What is the focus of the practical investigation?

  How resistance varies with applied voltage
• What are the variables in the investigation?

  • Independent variable: Voltage across the component
  • Dependent variable: Current through the component
  • Control variable: Temperature of the circuit
• What is the independent variable in the investigation?

  Voltage across the circuit component
• What is the dependent variable in the investigation?

  Current flowing through the circuit component
• What is the control variable in the investigation?

  Temperature of the circuit
• Why is it important to control the temperature in the investigation?

  To ensure consistent resistance measurements