Table of Contents
- 1 What is the rule for resistance in a DC series circuit?
- 2 What happens if the resistance is greater than the voltage?
- 3 What is the effect of resistance on a DC circuit?
- 4 Why does higher resistance mean higher voltage?
- 5 Why does higher voltage have less resistance?
- 6 Why does resistance increase with voltage?
- 7 Why do we need to turn off the supply first?
- 8 How do you know if a circuit is a load or resistance?
- 9 What is the relationship between current and voltage and resistance?
What is the rule for resistance in a DC series circuit?
UNDERSTANDING & CALCULATING SERIES CIRCUITS BASIC RULES The same current flows through each part of a series circuit. The total resistance of a series circuit is equal to the sum of individual resistances. Voltage applied to a series circuit is equal to the sum of the individual voltage drops.
What happens if the resistance is greater than the 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.
What is the effect of resistance on a DC circuit?
The effective (rms) value of an alternating current has the same average power loss equivalent to a direct current flowing through a resistive element. Resistance is the opposition to current flowing around a circuit. Low values of resistance implies a conductor and high values of resistance implies an insulator.
Why must power be turned off when measuring the resistance of a circuit with a multimeter?
A resistance measurement must be performed with the power off. The way that a meter measures resistance is that it actually puts a small current across the probes and measures the resulting voltage. The resistance reading is meaningless if there is already voltage on the thing you’re measuring.
Why is voltage different in series circuit?
In series circuits, the resistor with the greatest resistance has the greatest voltage drop. Since the current is everywhere the same within a series circuit, the I value of ΔV = I • R is the same in each of the resistors of a series circuit. So the voltage drop (ΔV) will vary with varying resistance.
Why does higher resistance mean higher voltage?
Ohm’s law states that the electrical current (I) flowing in an circuit is proportional to the voltage (V) and inversely proportional to the resistance (R). Similarly, increasing the resistance of the circuit will lower the current flow if the voltage is not changed.
Why does higher voltage have less resistance?
The lower current that accompanies high voltage transmission reduces resistance in the conductors as electricity flows along the cables. This means that thin, light-weight wires can be used in long-distance transmission.
Why does resistance increase with voltage?
In other words, the current is directly proportional to the voltage and inversely proportional to the resistance. So, an increase in the voltage will increase the current as long as the resistance is held constant. If the current is held constant, an increase in voltage will result in an increase in resistance.
How does DC affect voltage?
Alternating current is generated by electrons flowing in alternating directions. Direct current is generated by electrons flowing in only one direction. AC is also called mains electricity, household current, domestic power, line power, or wall power because it is the voltage supplied by a wall outlet.
Why should the power supply be turned off during readings?
Because the meter depends on having full control of the amount of current passing through the circuit whose resistance is being measured. If there is any additional current, the resistance reported by the meter will be inaccurate.
Why do we need to turn off the supply first?
The very first thing to do in case of an electrical fire is to cut the power supply at the source. Flip the switch on your home’s circuit breaker box and cut the supply. This will stop the fire on time and reduce the risk of shocks if you are trying to put out the fire.
How do you know if a circuit is a load or resistance?
A circuit’s wiring and connections should have little or no resistance and all voltage should be used through the load. The “load” is any device using the power, such as lighting, a starter motor, window motors, horns, fuel injectors, etc. Measure after a load and the available voltage is lower than before the load.
What is the relationship between current and voltage and resistance?
The first, and perhaps most important, relationship between current, voltage, and resistance is called Ohm’s Law, discovered by Georg Simon Ohm and published in his 1827 paper, The Galvanic Circuit Investigated Mathematically.
What is the difference between voltage drop and resistance?
If resistance occurs in the circuit, less voltage is available for the load to operate. If the circuit is functioning properly, all voltage will pass directly to the load and your meter will register an acceptable reading. Voltage drop is the amount of electrical pressure lost or consumed as the voltage pushes through a load or resistance.
What is the difference between DC voltage and DC current?
DC Voltage is the constant voltage source. In case of Direct Current, the polarity will never reverse or changed with respect to time, whereas the flow of current can vary with time. As in reality, there is no perfect condition. In case of the circuit where free electrons are flowing, it is also true.