[Search Doc Brown's science website]

SITEMAP   School-college Physics Notes: Electricity 3.7 Division of p.d. in a circuit

UK GCSE level age ~14-16 ~US grades 9-10 Scroll down, take time to study content or follow links

Electricity Section 3: 3.7 How the total potential difference is split between resistances in series

Doc Brown's Physics exam study revision notes: Explaining and verifying by calculation, how the potential difference (p.d.) is split (divided, shared) between resistances in series i.e. the effect of two (or more) resistors in series

INDEX for electricity section 3 notes on current, voltage, resistance, energy & charge transfer in circuits


3.7 A little more on potential difference - effect of two resistors in series - explaining and verifying by calculation, how the potential difference is split between resistances in series

circuit diagram showing how a p.d. is split between two resistors wired in series

The circuit 41 shows two resistors wired in series, so how is the total p.d. divided or shared between the two resistance wired in series.

This circuit can be used to investigate and confirm the correctness of the following theoretical calculations.

On the right is shown what happens to the p.d. going clockwise around the circuit (direction of convention current).

The potential store of the battery raises the potential difference of the charge to 12.0 V.

The total resistance = 10.0 + 5.0 = 15.0 Ω (you can add resistors up if wired in series)

Therefore the current flowing round all of this series circuit = I = V / Rtotal = 12.0 / 15.0 = 0.80 A

As the charge passes through the 1st resistor R1, it loses energy and the p.d. falls by 8 V to a p.d. of 4 V.

Calculation to confirm this:  V1 = I x R1 = 0.80 x 10.0 = 8.0 V

As the charge passes through the 2nd resistor R1, it loses energy again and the p.d. falls by 4 V to a p.d. of 0 V.

Calculation to confirm this:  V2 = I x R2 = 0.80 x 5.0 = 4.0 V

As long as there is a complete circuit, the process repeats itself through any number of resistors.

What is clear is the total p.d. for the circuit is split into a p.d. ratio identical to the resistor ratio.

V1 : V2 is the same ratio as R1 : R2

You can also say that since E = QV, twice as much energy is released by resistor R1 (p.d. 8 V) than R2 (p.d. 4 V) for the same total current, the same total charge transferred, but the lower the p.d. the less potential energy carried by the charge.

INDEX of electricity section 3 notes on current, voltage, resistance, energy & charge transfer in circuits including Ohm's Law investigations


Keywords, phrases and learning objectives for ? electricity

Be able to explain and verifying by calculation (and experiment), how potential difference is split shared divided between resistances in series.

Be able to describe the effect of two resistors in series on the p.d. across these resistors wired in series.


WHAT NEXT?

TOP of page

INDEX for physics electricity section 3 notes on current, voltage, resistance, energy & charge transfer in circuits

ALL my electricity and magnetism notes

email doc brown - comments - query?

INDEX of all my PHYSICS NOTES

BIG website and using the [SEARCH BOX] below, maybe quicker than navigating the many sub-indexes


Basic Science Quizzes for UK KS3 science students aged ~12-14, ~US grades 6-8

BiologyChemistryPhysics for UK GCSE level students aged ~14-16, ~US grades 9-10

Advanced Level Chemistry for pre-university age ~16-18 ~US grades 11-12, K12 Honors

Find your GCSE/IGCSE science course for more help links to all science revision notes

Use your mobile phone in 'landscape' mode?

INDEX of electricity section 3 notes on current, voltage, resistance, energy & charge transfer in circuits including Ohm's Law investigations

SITEMAP Website content Dr Phil Brown 2000+. All copyrights reserved on Doc Brown's physics revision notes, images, quizzes, worksheets etc. Copying of website material is NOT permitted. Exam revision summaries and references to GCSE science course specifications are unofficial.

Using SEARCH some initial results may be ad links you can ignore - look for docbrown

TOP OF PAGE