Electrical Cells

Electrical Cells • Energise me - lesson 5

Electrical Cells Date Connector: (Level 4) Name the different forms of energy.

Batteries • An electrical cell is another name for a battery. • Make a list of as many things that you can think of that use batteries, for example a mobile phone.

Different Types • In your lists most of you would have had batteries that you either use again or throw away. • These are called RECHARGEABLE and DISPOSABLE. • Write a definition of what these words mean.

Rechargeable Cells • A rechargeable cell or battery allows you to plug it in to the mains supply and 're-energise' • All this means is that you are replacing the electrical energy!

Disposable Cells • A disposable cell has a fixed amount of electrical charge, once this charge has been transferred to something it cannot be replaced. • When all the electrical energy has been transferred the battery is thrown away.

Task 1 • You work for an advertising company and have been asked to produce a slogan for their new brand of rechargeable batteries. • Make sure your slogan explains the differences between rechargeable and disposable!

What happens to disposable batteries? • We already said that disposable means that we throw it away when we are finished, where do these batteries end up?

Landfill Sites • Anything which is not recyclable is sent to a landfill site where it is buried under tonnes of rubbish. • Batteries contain some dangerous chemicals, why would you not want these crushed?

Recycling • Some supermarkets now have recycling bins just for batteries.

Disposable V Rechargeable Task 2 Use the table to write a paragraph to explain the advantages and disadvantages of the different cells.

Which Battery lasts the longest? • You have seen the adverts on TV, most companies say their battery will last longest. We are going to plan an experiment to test the following Hypothesis • "I think the Duracell battery will last the longest. I also believe that the more expensive the battery the longer it will last" • Write down this hypothesis in your book.

Variables • Independent variable (What's changed?) • Dependent variable (What's measured?) • Control variable (What needs to be kept the same?)

Variables • Independent variable (What's changed?) • The make of battery. • Dependent variable (What's measured?) • The time it takes for the battery to run out of charge. • Control variable (What needs to be kept the same?) • The same bulb, same stopwatch

Task 3 -Part 1 • Write a short method to explain how you would do your experiment, remember to explain how you would make sure the your experiment is REPEATABLE.

Example I experimented by testing the power of four different brands of batteries. I did this by hooking up the batteries to a light bulb. I then kept track of the length of time each bulb stayed lit. I tested two batteries from each of the four brands of batteries. How good is this method? What level would you give it? Now level the persons work next to you using the sheets in your book!

Task 3 - part 2 • After the testing was completed the following results were recorded: The Duracell battery lasted the longest, 101 hours and 20 minutes; Energizer battery, second, 99 hours and 17 minutes; Eveready battery, third, 28 hours and 30 minutes, and last but not least was the BA 30 batteries, 25 hours ad 58 minutes. • Is this the best way of recording results? • Turn this information into a table. • What do these results tell you?

Review • Hot seat challenge • Write down three questions. • A 'what.....' question is worth one point • A 'how.....' question is worth two points • A 'why.....' question is worth three points

Electrical Cells