1. Resistivity R = ρ L/A Resistivity of copper is 10 -8 Ωm Resistivity of glass is 10 12 Ωm

2. Batteries in Series 4 V 3 Ω 1 Ω 1a) What is the overall EMF? 1b) What is the current in the circuit? 8V 2 amps

3. Batteries 4 V 12 V 3 Ω 1 Ω 2a) What is the overall EMF? 2b) What is the current in the circuit? 8 V 2 amps

4. Design a Circuit to Divide Voltage 3) How many volts are released across the open leads? 12V 3Ω3Ω 3Ω3Ω?? Volts 6 V

5. Ohmic Conductors 4) For an ohmic conductor, if the voltage is doubled without changing the resistance, the current will: a)Decrease by a factor of 4 b)Decrease by a factor of 2 c)Increase by a factor of 2 d)Increase by a factor of 4 

6. Ohmic Conductors 5) If a 60 Watt bulb operates at 120V, what is the resistance of the bulb? a)2 Ω b)30 Ω c)240 Ω d)720 Ω e)7200 Ω 

7. In Parallel 6) If 3 bulbs are in parallel and the center bulb burns out, what happens? a)All bulbs go out. b)Intensity of other bulbs decreases. c)Intensity of other bulbs increases. d)Intensity of other bulbs remains same. e)More current is drawn from the source. ***************************************************************************************

8. Power 7) How much energy is dissipated as heat in 20 seconds by a 100Ω resistor at 0.5 A? a)50J b)100J c)250J d)500J e)1000J 

9. 8. What is the resistance at 4 volts? I (amps) V (volts) 2.0 4.0 I (amps) V (volts) 2.0 4.0 -------------------------- R = V/I = 4/3 = 1.3Ω

10. 9. What is the path followed by a positively charged sphere dropped between two charged plates? O

11. 10. What is the direction and strength of the electric field between the two plates?  E = 2500 N/C

12. What is the: 2 cm + 5 C + 7 C A. Force between the two charges? B. Electric field at the point between the two charges? C. Voltage at the point between the two charges? D. If the charges are brought to a distance of 0.5cm, what happens to the electric force between them? A. 7.88 x 10 14 N repulsion F B. 1.8 x 10 14 N/C  C. 1.8x10 12 V D. 1.26 x 10 16 N