1. P1a Topic 10 Internal Assessment

2. Diagram of Electric Motors Coil of Copper WireMagnet Split-Ring Commutator

3. Energy Transfers 1.List the energy transfers for the following machines. 2.Identify the useful energy output and the wasted energy output. a)Firework b)Battery-Operated Radio c)Electric Motor d)Light Bulb e)Hairdryer

4. Units of Measurement in Physics Voltage ( ) Current ( ) Resistance ( ) Power ( ) Charge ( ) Energy ( )

6. Physics Formulae Voltage = Current x Resistance –V = I x R Power = Current x Voltage –P = I x V Charge = Current x Time –Q = I x t Energy = Charge x Voltage –E = Q x V Energy = Current x Voltage x Time –E = I x V x t Energy = Power x Time –E = P x t Cost of Electricity = Power x Time x Cost of 1 kWh

7. Which line of best fit would you use to show this pattern? Best curve.  What would an estimate for 7V be? Why is this only an estimate?

8. Capacity (batteries) = Current x Time –Capacity = I x t Payback Time = Installation Cost Annual Saving Efficiency = Useful Output x 100 Total Input

9. Voltage, Current, and Energy To transfer a lot of electrical energy you either need a high voltage or a high current –P = I x V The problem with high current is the loss (as heat) due to the resistance of the cables –P = I 2 x R It is much cheaper to increase the voltage This keeps current low, meaning less wasted energy (higher efficiency)

10. Practical Skills Variables –Independent and Dependent –How are they set up in a table? on a graph? Emphasis on ‘accurate and reliable results’ –Concept of fair testing –Repeating the experiment

11. Tables and Graphs –How are anomalies identified? –How can the problem of anomalies be eradicated? Always draw a scatter graph unless told otherwise –Lines / Curves of Best Fit always included Label axes / Column headings with correct units

12. Paying up Work sheet P1a. 10.5 (1 and 2)

13. What are the benefits of using energy more efficiently?