Exam 4 We’ll grade it tomorrow afternoon We’ll grade it tomorrow afternoon The problem where you...

Exam 4 We’ll grade it tomorrow afternoon The problem where you had to had to

find n for a hydrogen atom after absorbing a photon . . . Reduce points possible by 9 points, grade out of 3 points.

Final Exam All Finals week in the testing centerSame format as midterms but no free

response- one page of notes- bring a calculator, scratch paper, pencils, erasers

Final Exam - 16 multiple choice– 2 problems from each unit like problems on

midterms If I asked a question about pressure change in

isothermal, be prepared to do isovolumetric, etc. If I asked a question about a lens, I might ask a

similar one about a mirror, etc. May be similar to a free response question

– 2 problems from each midterm with different numbers

Other Announcements SPS Finals Review

– 6-7 in the underground lab Go to the bottom floor of ESC, middle of

hallway running along north of building Door to the right of a small staircase going

up Open door, go all the way down the stairs

– Food at 5 Course Evaluations

– extra credit 20/1 point quiz

Rate the Tutors

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Rating form and photos of tutors:

http://gardner.byu.edu/tas/tutorrating.php

Requested Review Energy of photon vs wavelength

Energy of atom with a given n

Unit 2 ReviewIdeal Gas—PV=nRT—Watch units

W work done by gas vs. on gas

Adiabatic, constant V, T and P

Thermal equilibrium—Entropy

Unit 2 ReviewHeat --Internal energy – degrees of freedom

1st and 2nd laws of thermodynamics

Temperature change: Q=mcTPhase change: Q=mLRadiation, convection, conduction

In an ideal gas, if you double the volume of the container, while keeping the temperature and the number of molecules the same, the pressure in

the gas A. DecreasesB. Stays the sameC. Increases

Suppose we have two jars of gas, one of helium and one of oxygen. If both jars have the same volume, and the two gases are at the same pressure and temperature, which jar contains the greatest number of molecules?A. Jar of helium

B. Jar of oxygenC. Both jars contain the same number.

Consider both gases to obey the ideal gas law. Also note that the mass of an oxygen atom is greater than the mass of a helium atom.

Cwater=4186 J/kg oC Cgold=129 J/kg oCWhich heats up faster using the same heat source?

A. 1 kg waterB. 1 kg goldC. They both heat up at the same rate.

TmcQ Q is energy transferred

Put 100g Al at 100o C into 500g water at 20o C. What is the final T?cAl=900 J/kg oC cH2O=4186 J/kg oC

What will the final T be? A. 100o

B. 97o

C. 20o

D. 23o

E. 60o

The first law of thermodynamics

∆Eint = Q + W

The internal energy of an ideal gas depends only on the temperature of the gas.

Change of internal energy = heat put into system + work done on system

True or False: Given two different objects, the one with

the higher temperature contains more heat.

(a) T(b) F

The path shown below is adiabatic (Q = 0). The change in internal energy of the gas is

A. PositiveB. NegativeC. zero

P

V

In the path shown, the change in internal energy of the gas is

P

VA. NegativeB. PositiveC. Zero

In the path shown below, the gas returns to its original state. The net change in internal energy is

P

VA. PositiveB. negativeC. zero

In the path shown below, the heat Q put into the gas is

(a) negative.(b) zero.(c) positive.

P

V

In the path shown below, the gas returns to its original state. The heat put into the gas isP

V

A. PositiveB. negativeC. zero

One of the P-V curves below is for an isothermal process. The other

is for an adiabatic process. Which is adiabatic?

P

V

A

B

Two gases in separate containers have equal volumes, equal numbers of

molecules, and the same internal energy Eint. However, one gas is monatomic and

the other is diatomic. The pressure of the diatomic gas is

A. Less than that of the monatomic gas.

B. The same of that of the monatomic gas.

C. Greater than that of the monatomic gas.

The second law of thermodynamics says for a heat engine

A. You can’t get more work energy out than you consume in heat

B. You can’t get out all of the heat energy as work

C. You will get out more work energy than you consume in heat

Did you know, for example, that the two greatest intellectual achievements of the last century, the general theory of relativity and quantum mechanics, are in some points in conflict with each other. They cannot both be right in every detail. These are not my words, but the words of Stephen Hawking, the great British physicist. Yet, scientists rely on both of these theories every day to advance scientific knowledge, knowing that some day the differences will be understood, reconciled, and corrected.

So it is with the gospel and our testimonies, yours and mine. This is not to suggest that the gospel is imperfect, but our understanding of it sometimes is. Like the scientist that uses relativity and quantum mechanics, we do not discard the gospel or our testimony because not every piece fits today.

Richard G. HinckleyProphetic PrioritiesBYU Devotional, May 15, 2007

Unit 3 Review Ray approximation

Reflection

Refraction-Snell’s Law

Unit 3 Review Mirrors-equations and drawing principle

rays

Lenses-equations and drawing principle rays

Unit 3 Review Real and virtual images

Magnification

Unit 3 Review Camera

Glasses

Magnifying glass

Unit 3 Review Microscope

Telescope

Unit 3 Review Double and Single slit interference

Diffraction Grating

Unit 3 Review Thin film interference

Telescope (eye, radar dish, etc.) resolution

An object is placed in front of a concave mirror. Depending on the position of the object, the image formed may occur

A. Behind the mirror and be real

B. In front of the mirror and be virtual.

C. In front of the mirror and be upright

D. None of the above

Which of the following best describes the image for a thin diverging lens that forms whenever the magnitude of the object distance is less than that of the lens' focal length? A. Real and uprightB. Real and invertedC. Virtual and

uprightD. Virtual and

inverted

You are designing eyeglasses for someone whose near point is 60 cm. What focal length lens should you prescribe so that an object can be clearly seen when placed at 25 cm in front of the eye?

A. -15 cmB. -18 cmC. 18 cmD. 43 cmE. 60 cm

Group question: a flat glass microscope slide (n=1.5) with parallel sides in air is illuminated with green light (λ=520 nm). Light reflects off both surfaces. What do you see in top view (what is the combined light reflected off the slide)?

A. All darkB. All brightC. Dark and bright fringesD. Not enough

information is given

Discussion question: An oil film on water reflects different colors more or less brightly owing to interference, depending on the film thickness. All the colors reflect brightly where the film is thinnest. (thin compared to visible wavelengths, approximately zero but enough to have a reflected ray off the oil and the water), From this information, we can tell that the index of refraction of the oil is

A. Less than that of water.B. The same as that of

water.C. Greater than that of

water.

Discussion question: An interference pattern is formed on a screen by shining a planar wave on a double-slit arrangement (left). If we cover one slit with a glass plate (right), the phases of the two emerging waves will be different because the wavelength is shorter in glass than in air. If the phase difference is 180°, how is the interference pattern, shown left, altered?

A. The pattern vanishesB. The bright spots lie closer

together.C. The bright spots are farther

apart.D. There are no changes.E. Bright and dark spots are

interchanged

Unit 4 ReviewRelativity

Postulates of Special Relativity

Time Dilation

Length Contraction

Unit 4 ReviewRelativity

Lorentz Transformations

Adding velocities

Relativistic energy and momentum

After your friend drives past you in a car at a speed of 0.6 c, they turn on their headlights, and in their reference frame they measure the light traveling away from them at 2.9979x108 m/s. How fast will YOU measure the light traveling?

(a) 2.9979x108 m/s(b) Less than 2.9979x108 m/s(c) More than 2.9979x108 m/s

Your friend waves at you while they drive past you in a car. Who measures the proper time for how long they waved at you?

(a) You(b) Your friend(c) None of the above

Your friend waves at you while they drive past you in a car. Who measures the longer time for how long they waved at you?

(a) You(b) Your friend

Your friend waves at you while they drive past you in a car. Who measures the proper length of their car?

(a) You(b) Your friend(c) None of the above

Your friend drives past you in a car traveling at a velocity of 0.8 c. Your enemy travels past you in the opposite direction at a speed of 0.7 c. What velocity will your friend measure your enemy to be moving at?

(a) 0.1 c(b) c(c) 1.5 c(d) None of the above

Your friend drives past you in a car traveling at a velocity u. The car has a mass m. What is the momentum of the car?

(a) mv(b) mc(c) γmc(d) γmv (e) None of the above

Your friend drives past you in a car traveling at a velocity u. The car has a mass m. What is the kinetic energy of the car?

(a) (1/2) mv2

(b) mc2

(c) γmc2

(d) None of the above

Unit 4 ReviewQuantized Light - photons

Energy of a photon

Photoelectric effect

Compton effect

Unit 4 ReviewQuantum mechanics

de Broglie wavelength

uncertainty

Bohr atom

Which photon has more energy – a red photon with a wavelength of 650 nm or a blue photon with a wavelength of 450 nm?

(a) The red one(b) The blue one(c) They have the same energy(d) Not enough information is given

A photon with an energy of 2.1 eV hits a metal with a work function of 1.8 eV. What’s the kinetic energy of the electron kicked off by this interaction?

(a) 0.3 eV(b) Not 0.3 eV(c) What was the question?(d) Not enough information is given

A photon with a wavelength of 0.2 nm scatters off of an electron. The scattered photon comes out at an angle of 10 degrees from the direction that the incoming photon was traveling. What equation gives me the change in wavelength of the photon.

Which has a smaller de Broglie wavelength, an electron traveling at 10 m/s or a car traveling at 10 m/s?

(a) The electron(b) The car(c) An undisclosed third party

What is the uncertainty in velocity of a goldfish of mass m trapped in a bowl with linear dimensions l ?

What is the wavelength of the photon emitted when the electron in a hydrogen atom drops from the n=4 to the n=2 energy level?

Unit 4 ReviewNuclear Physics

Notation, atomic number, mass number

Half life

Unit 4 ReviewNuclear Physics

Decay types

Fission

Fusion