1. The big question: How do Kirchoff’s laws link with voltage, resistance and electrolysis Why are we learning this? One use of electrolysis and Kirchoff’s laws is hair removal $45 / £35 per 30 minutes

2. Electrolysis… Match up the words to the definitions (Wordwall)

3. Question to be asking ANSWER What are the baby and the dog doing? What is the facebook command it shows What is the voltage in the series circuit? What is the voltage in the parallel circuit?

5. Learning Objective: To combine understanding of Kirchoff’s laws with other concepts The big question: How do Kirchoff’s laws link with voltage, resistance and electrolysis A – Analyse circuits with different value resistors B – Predict currents using digital ammeters and Kirchoff’s laws C – Calculate current using same value resistors D – Investigate electrolysis

6. Electricity ALWAYS takes the easiest route If electricity cannot take the easiest route, it equally divides Make up this circuit Predict what current will be at A and B Measure current in A and B A B Same resistance

7. For these circuits, make them and test currents at A, B and C each time Also provide circuit diagrams A B ABC AB C C Provide an explanation for why changes each time

8. Learning Objective: To combine understanding of Kirchoff’s laws with other concepts The big question: How do Kirchoff’s laws link with voltage, resistance and electrolysis A – Analyse circuits with different value resistors B – Predict currents using digital ammeters and Kirchoff’s laws C – Calculate current using same value resistors D – Investigate electrolysis

9. So… This is a 12V cell Calculate current at each point if… (C) R1=R2=R3, and at 8 there is 10A (B) R1 is twice R2 and R3 and at 8 there is 10A (B) R1=R2, R3=R1+R2. At 8 there is 12A.

10. So… (A) This is a 12V cell Calculate the Relative values of R1, R2 and R3, if 4 is 5A, 3 is 15A and 2 is 20A 4 is 12A, 3 is 18A and 2 is 21A

11. So… (A) This is a 12V cell Calculate the Relative values of R1, R2 and R3, if 4 is 5A, 3 is 15A and 2 is 20A 4 is 12A, 3 is 18A and 2 is 21A

12. Learning Objective: To combine understanding of Kirchoff’s laws with other concepts The big question: How do Kirchoff’s laws link with voltage, resistance and electrolysis A – Analyse circuits with different value resistors B – Predict currents using digital ammeters and Kirchoff’s laws C – Calculate current using same value resistors D – Investigate electrolysis

13. How do you do it? A – You are given current for two resistors in parallel, and a voltage. You have to calculate the resistance B – You are given the different resistance of two resistors in parallel and a voltage. You have to calculate the current. C – You have two equal resistance resistors in paralell and a voltage. You have to calculate current

14. Test next lesson Read up on digital ammeters (hwk) Ext: q1 jun 2009