The human body produces a small amount of electricity as blood flows through our body. That is how we are able to take EEG, ECG,etc.
Does our body have resistance?
Answer is Yes, when our body or skin is dry, our resistance will be large. But, if it is wet, resistance decreases, and conductivity increases. So, it is not safe to touch electrical appliances when wet. Due to low resistance, there is a greater danger of us getting an electric shock.
Resistors in Various Forms
Resistor was invented by Otis Boykin
Thermistors: Resistors which are sensitive to heat.
- Resistors in Bulb
Electric bulb was invented by Thomas Alva Edison. These electric bulbs or incandescent lamps use resistors. They mainly work based on the heating effect of electric current. The resistor mainly used in bulbs is tungsten. Since tungsten filament has high resistance, while converting electrical energy into light energy, it also produces heat energy. Advanced LED lights can be used to replace incandescent lamps as they require less power to work and don't waste electrical energy in the form of heat.
- Carbon Resistor
Carbon resistors are widely used in electronic and electrical devices. They are small in size. The value of resistance can be found in the colour codes on them. A carbon film resistor generally has a resistive element made from a carbon film deposited on an inert substrate.
- Rheostat
Rheostat is a variable resistor which is widely used in electric circuits to control the current. Rheostats are called wire wound resistors since they are made by wrapping a large number of nichrome wires across a ceramic core. The core behaves like an insulator.
Difference between Voltmeter and Ammeter.
- Voltmeter
Voltmeter is the instrument used to measure voltage.
- Ammeter
Ammeter is the instrument used to measure electric current.
As a student you can see and may have used these instruments in your physics laboratory.
Note: Contents published here has been taken from various sources for reference purpose. Readers are requested to do their own study before using them in any medium.
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