- Is resistance directly proportional to length?
- What is high and low resistance?
- What is the relationship between current and resistance?
- Why does the heater having low resistance get heated more?
- What is a bad resistance reading?
- What causes resistance?
- Does resistance affect temperature?
- How does temperature affect current?
- How does resistance affect heat?
- Does heat increase with resistance?
- What is the resistance of the heater?
- When resistance increases what happens to voltage?
- Which is better higher or lower resistance?
- Is resistance directly proportional to heat?
- Does high resistance mean low current?
- Is heat directly proportional to temperature?
- Does more current mean more heat?
- What happens if resistance is too high?
- Why do heating elements have high resistance?
- Is high resistance dangerous?
- What is the heating effect of current?
Is resistance directly proportional to length?
Consistent with the discussion above, this equation shows that the resistance of a wire is directly proportional to the length of the wire and inversely proportional to the cross-sectional area of the wire..
What is high and low resistance?
The wires which allow electricity to flow very smoothly are said to have low resistance. the wires which do not allow electricity to flow very smoothly are said to have high resistance.
What is the relationship between current and resistance?
The relationship between current, voltage and resistance is expressed by Ohm’s Law. This states that the current flowing in a circuit is directly proportional to the applied voltage and inversely proportional to the resistance of the circuit, provided the temperature remains constant.
Why does the heater having low resistance get heated more?
Dividing the square of the voltage by the circuit resistance means that as we lower the resistance we see more heat produced. … Because for that circuit, the little heater wire is the only thing in the circuit. Nothing else is limiting current flow through that little wire, so it gets warm – or even hot.
What is a bad resistance reading?
While you may not know exactly what the resistance of your particular motor should be, you do know that it should be more than zero! A resistance measurement of less than .5 ohms usually indicates a short circuit in the motor winding.
What causes resistance?
An electric current flows when electrons move through a conductor, such as a metal wire. The moving electrons can collide with the ions in the metal. This makes it more difficult for the current to flow, and causes resistance.
Does resistance affect temperature?
The more these atoms and molecules bounce around, the harder it is for the electrons to get by. Thus, resistance generally increases with temperature. … In some materials (like silicon) the temperature coefficient of resistivity is negative, meaning the resistance goes down as temperature increases.
How does temperature affect current?
The effect of heat on the atomic structure of a material is to make the atoms vibrate, and the higher the temperature the more violently the atoms vibrate. … The more the atoms jostle around in the material, the more collisions are caused and hence the greater the resistance to current flow.
How does resistance affect heat?
Resistance rises with temperature, because the electrons pick up energy with heat, move around more vigorously, there are more collisions with electrons attempting to pass through the conductor, These collisions release more energy, in the form of heat, further increasing the temperature of the conductor.
Does heat increase with resistance?
Heating a metal conductor makes it more difficult for electricity to flow through it. These collisions cause resistance and generate heat. … Heating the metal conductor causes atoms to vibrate more, which in turn makes it more difficult for the electrons to flow, increasing resistance.
What is the resistance of the heater?
Heaters are nearly purely resistive so 1500watts/120V = 12.5A, 120V/12.5A = 9.6 ohms. That would be the steady state resistance of a 120V 1500watt heater.
When resistance increases what happens to voltage?
This equation, i = v/r, tells us that the current, i, flowing through a circuit is directly proportional to the voltage, v, and inversely proportional to the resistance, r. In other words, if we increase the voltage, then the current will increase. But, if we increase the resistance, then the current will decrease.
Which is better higher or lower resistance?
Resistance measurements are normally taken to indicate the condition of a component or a circuit. The higher the resistance, the lower the current flow. If abnormally high, one possible cause (among many) could be damaged conductors due to burning or corrosion.
Is resistance directly proportional to heat?
This is exactly as you have stated, the heat is directly proportional to the resistance and the square of the current. Because the current term is squared in the power equation, the heat given off by the circuit is more highly dependent on the current flowing through it than the resistance.
Does high resistance mean low current?
The circuit with the higher resistance will allow less charge to flow, meaning the circuit with higher resistance has less current flowing through it. …
Is heat directly proportional to temperature?
1: The heat Q transferred to cause a temperature change depends on the magnitude of the temperature change, the mass of the system, and the substance and phase involved. (a) The amount of heat transferred is directly proportional to the temperature change.
Does more current mean more heat?
Current and Heat The electrons have a mass (however small), and when they move through the conductor, there are collisions that produce heat. The more electrons bumping into the atoms of the conductor, the more heat is created, so higher current generally means greater heat.
What happens if resistance is too high?
RESISTANCE is not affected by either voltage or current. It is either too low, okay, or too high. If resistance is too low, current will be high at any voltage. If resistance is too high, current will be low if voltage is okay.
Why do heating elements have high resistance?
You might think a heating element would need to have a really high resistance—after all, it’s the resistance that allows the material to generate heat. … Getting the maximum current flowing through a heating element is much more important than forcing that current through a large resistance.
Is high resistance dangerous?
Higher voltage allows for the production of higher, more dangerous currents. Resistance opposes current, making high resistance a good protective measure against shock. Any voltage above 30 is generally considered to be capable of delivering dangerous shock currents.
What is the heating effect of current?
When an electric current is passed through a conductor, it generates heat due to the hindrance caused by the conductor to the flowing current. The work done in overcoming the hindrance to the current generates heat in that conductor.