1. A child, with a mass of 35 kg, falls off the swing and hits the ground at a speed of 6 m/s. a)Calculate the momentum of the child as it hits the ground. 210 kg m/s b) After hitting the ground, the child slows down and stops in 0.25 s. Calculate the force exerted by the ground on the child. 840 N

2. Electric circuits L.O.:  To interpret and draw circuit diagrams using standard symbols.  Explain the following terms and remember their units: current, resistance and voltage.

3. Homework due on 5/11/10: workbook pages 62, 74 & 78 You should have already done: 56, 57, 61, 67, 68, 69, 75, 56.

4. After watching this clip, answer the following questions. 1.What is voltage (potential difference)? 2. What is the role of a cell in a circuit? 3.What are the units of current, voltage and resistance?

6. Make the following circuits, draw the corresponding circuit diagrams and write down your observations. In all cases, connect an ammeter in series and a voltmeter in parallel 1. One cell + one lamp 2. One cell + 2 lamps 3. Two cells + 1 lamp

7. Task: While you watch the following animation discuss the analogies between a circuit and a water pump.

8. Current in a Series Circuit