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physics_girl
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A galvanometer of coil resistance 50 ohms deflects full scale for a current of 3.5 mA. What series resistance should be used with this galvanometer to construct a voltmeter which deflects full scale for 35 Volts?
A galvanometer is a sensitive instrument used to detect and measure small electric currents. It works on the principle of electromagnetic induction and typically has a coil of wire suspended in a magnetic field. A voltmeter, on the other hand, is a device used to measure the potential difference, or voltage, between two points in an electrical circuit. While both instruments measure electrical currents, a galvanometer is more sensitive and is typically used in scientific experiments and research, while a voltmeter is used for general circuit analysis and troubleshooting.
A galvanometer works by using a magnetic field to deflect a coil of wire, which is connected to a needle or pointer. When an electric current passes through the coil, it interacts with the magnetic field and causes the coil to rotate. The amount of rotation is proportional to the strength of the current, allowing the galvanometer to measure the current's magnitude. The direction of rotation also indicates the direction of the current.
Yes, a galvanometer can be converted into a voltmeter by adding a series resistor to the circuit. The resistor is used to limit the amount of current passing through the galvanometer, as it is typically designed to measure only small currents. By selecting the appropriate resistor value, the galvanometer can be calibrated to measure voltage instead of current.
One advantage of using a galvanometer is its high sensitivity, which allows it to detect and measure very small currents. This makes it useful in scientific experiments and research where precise measurements are required. Additionally, galvanometers are relatively simple and inexpensive compared to voltmeters, which may have additional features and functions that are not necessary for basic current measurement.
Yes, there are different types of galvanometers, including moving coil, moving iron, and electrostatic. Moving coil galvanometers use a coil of wire suspended in a magnetic field, while moving iron galvanometers use a movable piece of iron instead of a coil. Electrostatic galvanometers use electric fields instead of magnetic fields to deflect a needle or pointer. Each type has its own advantages and is used for different purposes, such as measuring different types of currents or for specific applications.