Resistance Formula

What is Resistance?

The opposition or resistance offered by something to a current passing through or flowing via it is known as resistance. In other words, it defines the opposition that is developed to the passage of current through a conductor or circuit element.

Definition:

Resistance (R) is the property of a component or material that resists the flow of electrical current. It is defined as the ratio of voltage (V) applied across the component to the current (I) flowing through it.

The resistance of any object is determined by the relation,

resistance formula

In this,

v = Voltage across its ends

I = Current flowing through it

If the resistances are connected in series, the series resistance is given as,

resistance formula

If resistance is connected in parallel, then parallel resistance is given by

resistance formula

Where, R1, R2, R3 …… Rn is the given resistor. Resistance is in ohms (Ω).

The Formula of Resistance is used for calculating the resistance on any given number of resistors in the circuit. It can be used in a similar way to calculate the resistance in any given object.

Solved Problems 

Below are the problems based on resistance that may help you.

Problem 1: Calculate the resistance offered by the body if 2mA of current is flowing having a potential difference of 2V.

Solution:

Given:

I (Current) = 2mA,

V (Potential difference) = 2 V

The resistance is given by:

resistance formula

Problem 2: Find the resistance when 5 Ω and 2 Ω are connected in parallel.

Solution:

Given,

Resistance:

     R1= 5 Ω,

     R2 = 2 Ω

The parallel resistance is given as,

resistance

Resistance, which controls for a given voltage how much current will flow, is essential when designing and analyzing electrical circuits. It is one of the major fundamental keys to electrical components whereby it plays an important role both in electrical engineering and electronics.

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