Thursday 8 December 2011

Science Year 5 - Unit 5 Electricity

We depend on electricity in our daily lives. Electricity has made our lives easier and more comfortable. There are many sources of electricity. Many appliances in our homes and schools use electricity. However. we must be very careful when using electrical appliances. Why?



Some electrical appliances use dry cells to make them work. Dry cells produce electricity. There are also other sources of electricity such as accumulator, dynamo and solar cell. They are examples of batteries.

Accumulators are used in vehicles such as motorcycles, cars and lorries. Dynamos generate electricity. They are used to light up the bulb of bicycle. Satellites get their electricity from solar cells. Solar cells transform light energy into electricity. We can also get electricity from hydroelectric power sation.


An electrical circuit is made up of a power source, wires and other components such as a bulb and a switch. The dry cell is a source of electrical energy for the circuit. A switch is used to break or complete a circuit. The wire allows electricity to flow through the circuit. The bulb lights up because electricity flows through it.

Electricity is useful in our everyday life. Electrical appliances need proper handling because they can cause injury if they are not used properly. Mishandling of electrical appliances can cause. There are safety precautions that must be taken when using electrical appliances.
  • Do not touch switches with wet hands.
  • Do not connect too many electrical appliances to one power point.
  • Do not repair electrical appliances by yourself.
  • Do not use electrical appliances that are faulty.
     
Science Exercise 1 for Unit 5
 



Science Exercise 2 for Unit 5
 



Science Exercise 3 for Unit 5
 



Science Exercise 4 for Unit 5