Table of Contents

- 1 How do you find resistance with potential difference and current?
- 2 How do you calculate current and resistance?
- 3 How do you calculate the potential difference in a circuit?
- 4 How is potential difference calculated?
- 5 How is resistance calculated according to Ohm’s law?
- 6 How to calculate the current flowing through a 3 Ω resistor?

## How do you find resistance with potential difference and current?

Calculating resistance

- To 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 Ω
- If you plot a graph of current against potential difference for a wire, you get a straight line.

**What is the formula of resistance?**

The resistance formula is as follows: Resistance = voltage drop across a resistor/ current flowing through a resistor. R = \frac{V}{I} R = resistance (Ohms, Ω) V = voltage difference which is between the two ends of a resistor (Volts, V)

### How do you calculate current and resistance?

Here endeth the sermon ! From this, we conclude that; Current equals Voltage divided by Resistance (I=V/R), Resistance equals Voltage divided by Current (R=V/I), and Voltage equals Current times Resistance (V=IR). The important factor here is the temperature.

**What is the resistance of the LDR when the potential difference is 4V?**

At potential difference = 4V, current = 0.4, so Resistance = 4/0.4 = 10Ω

#### How do you calculate the potential difference in a circuit?

Multiply the amount of the current by the amount of resistance in the circuit. The result of the multiplication will be the potential difference, measured in volts. This formula is known as Ohm’s Law, V = IR.

**What happens to the potential difference across the LDR and the current in the LDR?**

An increase in light intensity decreases the LDR’s resistance and therefore the potential difference across the LDR will decrease.

## How is potential difference calculated?

**How do you calculate VI?**

Ohms Law is used extensively in electronics formulas and calculations so it is “very important to understand and accurately remember these formulas”.

- To find the Voltage, ( V ) [ V = I x R ] V (volts) = I (amps) x R (Ω)
- To find the Current, ( I )
- To find the Resistance, ( R )
- To find the Power (P)

### How is resistance calculated according to Ohm’s law?

Calculating resistance – Ohm’s Law The resistance of an electrical component can be found by measuring the electric current flowing through it and the potential difference across it. This equation, called Ohm’s Law, shows the relationship between potential difference, current and resistance: voltage = current × resistance

**What is the relationship between current and resistance?**

This equation, called Ohm’s Law, shows the relationship between potential difference, current and resistance: curriculum-key-fact voltage = current × resistance

#### How to calculate the current flowing through a 3 Ω resistor?

Find the current flowing through a 3 Ω resistor when a potential difference of 30 V is applied across it. Solution: Current (I) = V ÷ R; I = 30 V ÷ 3 Ω; I = 10 A

**How to calculate the voltage of a 10 Ma resistor?**

[Voltage (V) = Current (I) x Resistance (R)] V (volts) = I (amps) x R (Ω) Find the voltage applied across 15 kΩ resistors when 10 mA current flows through it. Solution: Voltage (volts) = Current (amps) x Resistance (Ω); V = 10 mA x 15 kΩ; V = 150 V