Questions and Answers
What relationship does Ohm's Law describe?
What is the unit of resistance according to Ohm's Law?
What happens to the current if the resistance is doubled?
What is a rheostat used for in an electric circuit?
Signup and view all the answers
Which equation represents Ohm's Law?
Signup and view all the answers
If the potential difference across a conductor is 1 V and the current is 1 A, what is the resistance?
Signup and view all the answers
The V-I graph for a nichrome wire shows what type of relationship?
Signup and view all the answers
What does the equation $V/I=constant$ signify in terms of resistance?
Signup and view all the answers
Study Notes
Circuit Setup
- Components required: nichrome wire, torch bulb, 10 W bulb, ammeter (0-5 A range), plug key, and connecting wires.
- Four dry cells (1.5 V each) connected in series with the ammeter, creating a gap in the circuit.
Ohm's Law
- Voltage-Current (V-I) graph of a nichrome wire shows a straight line, indicating a linear relationship between current and potential difference.
- Observations confirm that V/I remains consistent, represented by a straight line through the origin on the graph.
Historical Context
- Georg Simon Ohm discovered the relationship between current (I) and potential difference (V) in 1827.
- Ohm's Law states that V is directly proportional to I for a metallic wire, given constant temperature.
Mathematical Relationships
- Ohm's Law can be expressed as:
- ( V/I = constant )
- ( V = IR )
- Resistance (R) is defined as the constant ratio for a given metallic wire at a specific temperature.
Resistance Definition
- Resistance is the property of a conductor to impede the flow of electric charge, measured in ohms (Ω).
- 1 V across a conductor with 1 A current results in a resistance of 1 Ω.
Current and Resistance Relation
- From the equation ( I = V/R ), current through a resistor is inversely proportional to its resistance.
- Doubling the resistance results in halving the current.
Variable Resistance
- A rheostat is used in circuits to adjust resistance without altering the voltage source, thereby regulating current flow in practical applications.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
This quiz explores the principles of Ohm's Law through a practical experiment using nichrome wire and circuit components. Learn to set up a circuit and understand the linear relationship between current and potential difference. Test your understanding of the concepts presented in this activity.
