2.4 and 2.5
2.4
24 November 2010 10:12· 2.4 know some of the different ways in which electrical heating is used in a variety of domestic contexts
· Tell the person next to you… ...some electrical appliances in your house that change electrical energy directly into into heat energy Answers
· Electric kettle
· Electric cooker/oven
· Electric hot shower
· Electric room heater (probably not in Thailand though!)
· Toaster
· Rice cooker
· Sandwich maker
· Hairdryer
· Etc…
· Note: Microwave cookers are not an example of electrical heating. They produce use electricity to produce microwaves which make the water molecules in food vibrate more and heat the food up. 2.5 answers 24 November 2010 10:12
· 2.5 understand that a current in a resistor results in the electrical transfer of energy and an increase in temperature http://phet.colorado.edu/en/simulation/battery-resistor-circuit [cid:image001.jpg@01CCB40C.19692470] Answers
1. What happens to the rate of flow of electrons in the circuit? How do you know this?
· The rate of flow of electrons increases. The electrons are moving faster and turning the paddle wheel faster
2. What happens to the current in the circuit? How do you know this?
· The current also increases (current is the rate of flow of electrons!). The reading on the ammeter increases
· What happens to the temperature in the resistor? How do you know this?
· The temperature increases. The metal ions in the resistor vibrate faster and the reading on the temperature scale increases





