1. S3 Revsion

2. Forces – Worked Example Forces acting on a beam worked example 100N 3m 2m R1 P Moment = Force x Distance 100N x 5m = 500Nm Force R1 = Moment / Distance = 500Nm/2m R1 = 250N

3. Forces Problems 500KN 10m 2m R1 P 1000N 1m 5m R1 P 20KN 6m 4m R1 P

4. Voltage Divider – Worked example 5V 0V 5k 2k Vout Vout = R1/Rt x Vs Vout = 5000 / 7000 x 5 Vout= 3.5v

5. Voltage Dividers examples 5V 0V 7k 3k Vout 9V 0V 15k 20k Vout 12V 0V 5k Vout

6. Calculating Total Resistance 20 2 6 Calculate the total resistance Step 1 calculate the total resistance in parallel 1/RT = 1/R1+1/R2 1/RT = 2/12 + 6/12 1/RT = 8/12 OR 12/8 RT = 1.5 OHMS Total resistance is: RT = 20 + 1.5 Total resistance is 21.5 ohms

7. Calculating Total Resistance 20 10 20 50 120 30 5k 15 60

8. Heat Energy Calculate the heat energy of 5 litres of water in a kettle which has had its temperature raised from 20°c to 80°C (I litre of water a mass 1kg) Specific heat capacity of water is 4200 Eh= mc Δ T Eh = 5 x 4200 x 60 Eh = 1260000 J

9. Heat Energy 1. Calculate the heat energy of 10 litres of water in a kettle which has had its temperature raised from 40°c to 80°C (I litre of water a mass 1kg) Specific heat capacity of water is 4200 2. Calculate the heat energy of 2 litres of water in a kettle which has had its temperature raised from 40°c to 42°C (I litre of water a mass 1kg) Specific heat capacity of water is 4200 3. Calculate the heat energy of 15 litres of water in a kettle which has had its temperature raised from 60°c to 100°C (I litre of water a mass 1kg) Specific heat capacity of water is 4200

10. Mechanisms