What is resistance KS3?

The resistance is the ratio of potential difference to current. We use this equation to calculate resistance: resistance = potential difference ÷ current. For example, 3 A flows through a 240 V lamp.

What is the equation for resistance KS3?

This KS3 physics resource is perfect for students who need some support in calculating resistance using the formula resistance (Ω) = potential difference (V) ÷ current (A).

What are resistors BBC Bitesize?

A resistor is an electrical component that restricts the flow of electric current. When resistors are connected in parallel, the combined resistance of two or more resistors is less than that of either resistor by itself.

How do I measure resistance?

Resistance can be calculated by measuring the current and voltage using Ohm’s Law. As a result, a circuit’s resistance value can be determined if the current and voltage measured values are known. Analog multimeters and digital multimeters employ the measurement principle of Ohm’s Law to measure resistance.

What is the formula of resistance?

Resistance Formula 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)

What happens to resistance in parallel?

Resistors in parallel In a parallel circuit, the net resistance decreases as more components are added, because there are more paths for the current to pass through. The two resistors have the same potential difference across them. The current through them will be different if they have different resistances.

What is the difference between resistance and net resistance?

Resistors in series In a series circuit the total resistance across all of the components (the ‘net resistance’) increases as more components are added. The two resistors have the same current flowing through them. The potential difference across them will be different if they have different resistances.

What are the 4 factors of resistance?

There are 4 different factors which affect resistance:

  • The type of material of which the resistor is made.
  • The length of the resistor.
  • The thickness of the resistor.
  • The temperature of the conductor.

How to measure the resistance of a component?

To find the resistance of a component, you need to measure: 1 the potential difference across it 2 the current flowing through it More

Which is an example of a unit of resistance?

The unit of resistance is the ohm, and it has the symbol Ω (an uppercase Greek letter omega). For example, a 2 Ω component has a greater resistance than a 1 Ω component, and will reduce the flow of charge through it more effectively.

How is resistance related to area of cross section?

The relationship between resistance and the area of the cross section of a wire is inversely proportional. When resistance is increased in a circuit, for example by adding more electrical components, the current decreases as a result.

How is the current related to the resistance?

Current is the rate of flow of electric charge. A potential difference (voltage) across an electrical component is needed to make a current flow through it. There is a resistance to the flow of an electric current through most conductors.