Download Exam 2 Review

Exam 2 Review
General Comments
 There are many analogies between chapters 15 & 16 and 19 & 20 (i.e charge is
like current, Ampere’s Law is like the Biot-Savart Law, etc..), so if you
understand these analogies they will help you (but if you don’t understand them,
then don’t try to).
 You should review some properties from mechanical physics like the work energy
theorem, centripetal force, etc.. because you will most likely have to find the
velocity of a charged particle in an electric field/potential, or find the radius of a
particle in a magnetic field.
 Some people have said that they studied a lot and knew how to do most of the
problems, but still didn’t do very well on the exam. My recommendation is to
work as many of the problems at the end of the chapters as possible. But don’t
just memorize how to do the problems, understand what is going on in each step
of the problem and why each equation is being used.
 Another good study technique is to work a problem and then “tweak” somehow
(i.e if the magnetic field was changed/orientated how would this affect the
problem), and then try to find the answer.
 If you are able to do the problems well, then try to derive the equations found at
the end of the chapters.
 Remember to review problems done in class (both by me and in groups).
Chapter 19:
 Like poles repel, unlike pole attract
 Field lines leave from the north pole, enter the south pole
 How a particle moves in a magnetic field (i.e figure 19.6). Be able to calculate
the third quantity given the other two (ex given the force and velocity, find the
magnetic field)
 Which direction the force is orientated when a wire carries a current in a magnetic
filed (figure 19.10). Be able to find the third given the other two as stated above
 How to find the torque on a loop in a magnetic field
 Figure 19.19
 Ampere’s Law, the right hand rule for it (figure 19.24) and equation 19.11
 Calculate the force between two wires carrying currents (figures 19.28 and
19.29).. both magnitude and direction
 Be able to find the magnetic field (and it’s direction) for a circular loop (figure
19.30)
 Solenoids: calculate its magnetic field and what direction the field is in
 Problems: Conceptual Problems: 3,5,10,13,18,20
Problems:
2,3,6,8,18,19,21,24,27,30,31,32,34,38,42,46,47,49,47,49,53,58,61,
63
Chapter 20:
 In this chapter, concepts are VERY important, so understand the concepts
 Magnetic flux: how to calculate it
 Lenz’s law: know how to use it/what it does in certain situations as well as figures
20.14 and 20.15
 Faraday’s Law: be able to calculate the induced current or Emf and what direction
it will be going in
 Motional Emf: why figure 10.10 occurs
 Figure 20.11: be able to calculate all of the values and what direction the are in)
 Figure 20.23: understand them and be able to use them
 R-L circuits: be able to find the time constant and the current as a function of time
(very bottom of page 640)
 Be able to calculate the energy stored in a magnetic field
 Problems: Conceptual Problems: 2,5,12,13,15
Problems: 2,4,6,9,10,11,14,15,18,19,21,22,2329,36,40,44,46,48,53,61
Chapter 21:
 Transformers: basically understand the whole section and be able to use the
equations… what a step-up/down transformer is, how the current will change if
the voltage goes up, etc..
 How to calculate the average power per unit area (eq 21.27 and 21.28)
 The relationship between E and B (in terms of velocity, how they propagate, etc..)
 All of the examples and quick quizzes are pretty good to study
 Be able to calculate the frequency or wavelength of an EM wave
 Problems: 38, 40, 42, 45, 47, 49, 50, 51, 53, 54, 56, 57
Chapter 22:
 The difference between specular and diffuse reflection
 The law of reflection
 Snells law
 How rays will bend if they pass through certain media (i.e closer to the normal,
farther away, etc..)
 How to calculate the index of refraction
 All of the quick quizzes and examples are good things to study
 Problems: 6, 9, 12, 16, 18, 19, 20, 25, 27