1. Reading Quiz
A light bulb is connected to a battery so that current flows through the bulb, which gives off light. Choose the correct statement:
The amount of current going into the bulb equals the current leaving the bulb.
The amount of current entering the bulb is greater than the amount of current leaving the bulb.
The bulb is converting electric charge into light.

2. Physics Help Center NEXT EXAM Wednesday April 7th @7pm to 9pm
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Chapters 10,11,12,13,14,15

3. Summary of electric circuits:
The amount of current is the same at every place in a series circuit; I=q/t.
The power provided by the battery (P=IDV) is exactly equal to the power dissipated in the resistors (P=I2R).
Ohm’s Law applies to resistors: DV=IR
Series circuit: effective R = R1 + R2 + R3
Parallel circuit: effective R is

4. Fig. 13.3
Fig. 13.3

5. Fig. 13.1
Fig. 13.1

6. Fig. 13.2
Fig. 13.2

7. Fig. 13.4
Fig. 13.4

8. Summary 2
Fig. 13.p270b

9. Ohm’s Law applies to resistors: DV=IR
Battery increases energy of charges (DPE); voltage on battery is called “EMF”.
This amount of energy is expended in the resistor.
For a given battery (V) and resistor (R), the current is given by Ohm’s Law:
DV=IR
EMF
volts I V R
The unit of resistance is an Ohm.

10. Fig. 13.6
Fig. 13.6

11. Fig. 13.7
Fig. 13.7

12. Fig. 13.5
Fig. 13.5

13. A simple battery does which of the following:
Lecture Quiz 26 - Question 1:
A simple battery does which of the following:
A. It creates charges.
B. It does work on charges.
C. It creates energy.

14. Is the voltage drop the same across all three resistors?
Series Resistance
EMF= DV1 + DV2 + DV3 OR
V = IR1 + IR2 + IR3
= I(R1 + R2 + R3)
= I Rseries
Where Rseries = R1 + R2 + R3
EMF
volts R1 V R2 R3
Is the voltage drop the same across all three resistors?
Is the current the same through all three resistors?

15. Fig. 13.9
Fig. 13.9

16. What is the total resistance of this circuit?
Exercise 9
What is the total resistance of this circuit?
1.) 66 ohms
2.) 60 ohms
3.) 54 ohms
4.) 25 ohms
5.) 15 ohms
Fig. 13.p274a

17. What is the current that flows in this circuit?
Exercise 9
What is the current that flows in this circuit?
1.)10 amps
2.) 1 amp
3.) 0.1 amp
4.) 0.3 amp
5.) 0.03 amps
Fig. 13.p274a

18. Fig
Fig

19. V = I Reffective Parallel Resistors Effective resistance 1 2 3 V Where
EMF
volts 1 2 3 V
Where
V = I Reffective
How much current flows through the three resistors?
Is the voltage drop the same for all three resistors?

20. Exercise 12 What is the total resistance of this circuit? 1.) 72 ohms
Fig. 13.p274b

21. A . What is the current that flows in this circuit at point A?
1.)288 amps
2.) 1.5 amp
3.) 0.1 amp
4.) 0.5 amp
5.) 0.03 amps
Fig. 13.p274b

22. B. What is the current that flows in this circuit at point B?
1.)288 amps
2.) 1.5 amp
3.) 0.1 amp
4.) 0.5 amp
5.) 0.03 amps
Fig. 13.p274b

23. By placing electrical items in series they receive the same current
By placing all electric items in parallel they receive the same voltage
Fig
By placing electrical items in series they receive the same current

24. A volt meter has a high resistance so take very little current
Fig
A volt meter has a high resistance so take very little current

25. Fig
Fig
An Amp meter has very little resistance so take very little voltage

26. Summary of electric circuits:
The amount of current is the same at every place in a circuit; I=q/t.
The power provided by the battery (P=IDV) is exactly equal to the power dissipated in the resistors (P=I2R).
Ohm’s Law applies to resistors: DV=IR
Series circuit: effective R = R1 + R2 + R3
Parallel circuit: effective R is

27. Question 14
Fig. 13.p272g

28. For an “ohmic” resistor, V=IR, so P = I2R
The power provided by the battery (P=IDV) is exactly equal to the power dissipated in the resistors (P=I2R).
Power P= work/time
Power=DPE/t
=qDV/t
=IDV
=IV
For an “ohmic” resistor, V=IR, so P = I2R

29. Lecture Quiz #26 Question 2
Consider a standard flashlight which is turned on.
A. The batteries create electrons, which get used up in the light bulb.
B. Energy is created in the batteries, which is destroyed in the light bulb.
C. The power used up by the light bulb originates in the batteries.
D. The light bulb converts electrons into light.

30. Lecture Quiz: Question 3
How much current I runs through this circuit:
A Amps
B A
C A
D A
E A
3 V
4 W
4 W

31. Lecture Quiz: Question 4
For three resistors in parallel, choose the correct statement:
A. The current and the voltage across all three are the same.
B. The voltage drop and the power dissipated across all three are the same.
C. The energy given up per electron is the same for all three.
D. The current through one resistor is the same as the current through the battery.
EMF
volts 1 2 3

32. What does the battery do? Where does the light energy come from?
The amount of current is the same at every place in a (single-loop) circuit; I=q/t. I
Battery
Light Bulb I I
What does the battery do?
Where does the light energy come from?
Why do batteries burn out? I