Energy Use In Electrical Appliances | Energy | Physics | FuseSchool

Do you ever have arguments at home about leaving appliances on and wasting electricity?
In this video we are going to look at measuring energy use, in electrical appliances.
The unit of energy is the Joule (J). However, when dealing with electricity, we actually use Watts (W).

A Watt is a measure of power where 1 Watt is equal to 1 Joule per second
So a 100W light bulb uses 100J of energy every second

An electrical device will have a power rating. This is the amount of electrical energy the device needs to work.
We can calculate how much electrical energy a device transfers, by multiplying the power rating (W) by the amount of time the device is on for (in hours)
The unit of electrical energy transferred is the Watt Hour (Wh).

This is likely to be a very large number, so we usually give the number as kilowatt hours where 1kilowatt hour is equal to 1000 Watt hours.
Let’s look at an example.
A computer has a power rating of 250W. If it is used for 6 hours how much energy is transferred to it?
Can you substitute the values into our equation?
So how much would that cost to use?
To work this out we have to know how much a kWh costs. This differs between different countries, different companies within a country, and even different tariffs from the same company.
A whole office of computers… the price starts to clock up quite quickly. And that’s before we think about the lights, and charging our phones.

Animation & Design: Reshenda Wakefield
Narration: Dale Bennett
Script: Bethan Parry

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  1. noway noway on April 29, 2021 at 12:11 am

    this is very good for exams and tests

  2. Fatima Tariq on April 29, 2021 at 12:14 am

    Tysm for such an awesome video.
    U just gained a new subscriber.
    Keep up the Great work 👍

  3. Ella Forrest on April 29, 2021 at 12:15 am

    This is my lockdown homework

  4. Shahin Ahmed on April 29, 2021 at 12:20 am


  5. SteelBlade Racing on April 29, 2021 at 12:22 am

    I don’t like it

  6. Laynna Rios on April 29, 2021 at 12:33 am

    Subtitles in English, please! I’m Brazilian.

  7. Mo_Bikes on April 29, 2021 at 12:37 am

    Good because it shows an xbox instead of ps4

  8. Alfie Pickering-Ford on April 29, 2021 at 12:47 am

    ============================================================================================================This is how many people are doing this for homework

  9. Felix Alejandro on April 29, 2021 at 12:50 am

    Winner of a video, I’ve been looking for "make electricity at home" for a while now, and I think this has helped. Have you ever come across – Diyadison Penhloe Blaster – (just google it ) ? It is a smashing one off guide for generating your own electricity minus the normal expense. Ive heard some decent things about it and my cousin got cool success with it.

  10. M i s t on April 29, 2021 at 1:01 am


  11. Mr. GAP - Uɴɪᴍᴀɢɪɴᴇ Tᴇᴄʜ on April 29, 2021 at 1:02 am

    *I am first Today*

  12. Tetsu de Rothchild on April 29, 2021 at 1:04 am
    It is clear that cars r emitting far less then electricity consumption.
    So let me get this straight we stop cars emitting co2 but we move to electricity? Still emitting co2 no?
    Perhaps more.
    how much electricity is used to power a car?
    How much is that energy emitting?
    Boycott electric movement its a farce.
    Its like green energy. Costs loads to produce a little energy y not invest in nuclear reactors? Squeaky clean uk with no death penalty for 50 years plus has 15 nuclear reactors.
    Boycott the electric movement

  13. shivananthan subbetshanaa on April 29, 2021 at 1:07 am


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