What is the formula for resistance?
If you know the total current and the voltage across the whole circuit, you can find the total resistance using Ohm’s Law: R = V / I. For example, a parallel circuit has a voltage of 9 volts and total current of 3 amps. The total resistance RT = 9 volts / 3 amps = 3 Ω.
What is the formula to calculate the unknown resistance?
Each time you can calculate the unknown resistance using the formula:unknown resistance(a)=known resistance(b)*L/M. The value is found to be the same for all values of known resistance.
How do you calculate resistance in physics?
Calculating resistanceTo find the resistance of a component, you need to measure:The resistance is the ratio of potential difference to current. For example, 3 A flows through a 240 V lamp. resistance = 240 ÷ 3 = 80 ΩIf you plot a graph of current against potential difference for a wire, you get a straight line.
What is resistance and example?
Resistance is defined as a refusal to give in or to something that slows down or prevents something. An example of resistance is a child fighting against her kidnapper. An example of resistance is wind against the wings of a plane.
What is the unit of resistance?
Siemens per meterElectrical conductivityOhm meterElectrical resistivity
What is current formula?
Current is usually denoted by the symbol I. Ohm’s law relates the current flowing through a conductor to the voltage V and resistance R; that is, V = IR. An alternative statement of Ohm’s law is I = V/R.
How do you calculate ohms?
Ohms Law and PowerTo find the Voltage, ( V ) [ V = I x R ] V (volts) = I (amps) x R (Ω)To find the Current, ( I ) [ I = V ÷ R ] I (amps) = V (volts) ÷ R (Ω)To find the Resistance, ( R ) [ R = V ÷ I ] R (Ω) = V (volts) ÷ I (amps)To find the Power (P) [ P = V x I ] P (watts) = V (volts) x I (amps)
How do you calculate resistance of a cable?
The electrical resistance, R of this simple conductor is a function of its length, L and the conductors area, A. Ohms law tells us that for a given resistance R, the current flowing through the conductor is proportional to the applied voltage as I = V/R.
How do you calculate resistance in parallel?
The sum of the currents through each path is equal to the total current that flows from the source. You can find total resistance in a Parallel circuit with the following formula: 1/Rt = 1/R1 + 1/R2 + 1/R3 + If one of the parallel paths is broken, current will continue to flow in all the other paths.
What is a resistance in physics?
Resistance is a measure of the opposition to current flow in an electrical circuit. Resistance is measured in ohms, symbolized by the Greek letter omega (Ω). Ohms are named after Georg Simon Ohm (1784-1854), a German physicist who studied the relationship between voltage, current and resistance.
What is Ohm’s law Resistance?
Ohm’s law: an empirical relation stating that the current I is proportional to the potential difference V, ∝ V; it is often written as I = V/R, where R is the resistance resistance: the electric property that impedes current; for ohmic materials, it is the ratio of voltage to current, R = V/I ohm: the unit of
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.