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A rheostat is a variable resistor and these control the flow of current.
Wiki User
∙ 11y ago
Wiki User
∙ 14y agoIt limits the current flow according to Ohms law.
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When the voltage applied to the rheostat is doubled then tripled what happens to the rheostat?
The heat released by the rheostat with double the voltage will quadruple. When voltage is tripled, the power loss is 32 or 9 times that before. A rheostat is a kind of variable resistor. Since E = IR (voltage equals current times resistance), then I = E/R (current equals voltage divided by resistance). If the voltage is doubled and the resistance stays the same, then--you can see by the formula--the current would double. Now, power dissipated by a resistor is related to the product of the current and voltage (P = IE). But since a doubling of voltage produces also a doubling of current, double the current results in 2X2=4 times the power (heat) loss.
What is the purpose of a rheostat in the determination of an unknown resistor?
In a bridge circuit the unknown resistor is compared to the rheostat. When the meter across the bridge reads in the middle the unknown and the rheostat are the same value.
What is a device that measures the strength of an electric current?
ammeter
How can the magnetic field strength of an electromagnet be reduced?
Either increasing the size of the current (in amps) or the number of turns of wire wrapped around the core will make a stronger magnet. A larger current will make a stronger magnet (up until too much makes the wire melt!). Increasing the voltage forces more current through the electromagnet.
Is it true that The strength of an electromagnet is easy to control?
yes it is easily controlled.
What is the rheostat?
It is a variable resistance device which control the flow of current
What are the colours of the positive and the negative terminals of the rheostat?
A rheostat is simply a variable resistor used to control current. It does not have a positive or a negative terminal.
Can rheostat run on AC current and DC current?
yes
What is the function of rheostat in this experiment?
A rheostat is the name given to a variable resistor when it is used to control current. When a variable resistor is used to control voltage, we call it a potentiometer.A rheostat is connected in series with a load, and two of its three terminals are used. A potentiometer is connected in parallel with the supply, and each of its three terminals are used.So the terms 'rheostat' and 'potentiometer' are the names given to describe the function of a variable resistor, not the variable resistor itself.
What is a microscope rheostat control?
That would control the lamp intensity.
What is the name of a variable resistor with 3 terminals?
It's called a 'variable resistor'. However, it can function as a 'rheostat' (to control current) when two terminals are connected, or as a 'potentiometer' (to control voltage) when three terminals are connected. The terms, 'rheostat' and 'potentiometer' do not describe the device itself, but how it is being used.
Explain the rheostat and its advantages in electric circuits?
Advantages in electric circuits : Advantages of using the rheostat in electric circuits is optional as you could just use the dial on the power-supply to vary the voltage (p.d.), and therefore the current. The advantage of using the rheostat is that you can control it to give you nice even numbers for the voltage.
When to use a rheostat?
Depending on the situation. The purpose of the rheostat is use to change the resistance of the circuit. The rheostat is use to define Ohm Laws the 2nd situation is use to find out what the fixed resistor's resistance. 3rd purpose : used to control the resistance of circuit. eg Radio
How does a rheostat make a current high?
The rheostat makes the current high by decreasing the resistance.....and as v=ir.. if r has been decreased and v remains constant than i will increase..
What does a dash rheostat do on a 1995 Mercedes e300d?
That is the dash light dimmer control switch.. Rheostat = Dimmer. Bright to dim.
Can you use a rheostat on ac motor?
Yes you can use a rheostat to control the speed of an ac motor as long as it is correctly sized (power). A better way would be to use a triac control.
How can a potentiometer be a rheostat?
A rheostat and a potentiometer are two different applications for the same device, a variable resistor. These devices have three terminals. Two terminals are connected across the complete resistor, while the third terminal is connected to a controllable wiper. The variable resistance is provided between the wiper terminal and either one of the other two terminals.When used to control current, it is called a rheostat. When used to control voltage, it is called a potentiometer.
