The correct answer is Ammeter.
Key Points
- An ammeter is the instrument used to measures the electric current in a circuit.
- Electricity is the flow of free electrons.
- Unit of Current - Ampere.
- Father of Electricity - Michael Faraday.
Additional Information
Ohmmeter
- The instrument used to measure the electrical resistance.
- Electrical resistance opposes the flow of electric current in a circuit.
- Unit of Resistance - Ohm
- Ohm's law states that the current through a conductor between two points is directly proportional to the voltage across the two points.
- V=IR, where (R) Resistance is the proportionality constant.
Thermometer
- An instrument used to measure the temperature.
- The first Mercury Thermometer was invented by Gabriel Fahrenheit.
Gyroscope
- The instrument used to measure or maintaining the orientation of angular velocity.
- Gyroscope was invented by Leon Foucault.
