Physics 231 lectures 19-24lynch/phy231_2010/review3.pdf · – Energy or power problemsEnergy or...

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Transcript of Physics 231 lectures 19-24lynch/phy231_2010/review3.pdf · – Energy or power problemsEnergy or...

Final Exam

A fi l ti i h d l d f ll ti f Ph i 231• A common final exam time is scheduled for all sections of Physics 231 • Time: 3pm-5pm, Thursday, May 5 .• Location : E100 Vet. Med. • This information can also be found on our course schedule page

• An alternate exam time will be scheduled for students who have• An alternate exam time will be scheduled for students who have conflicts with the regular time. – Three students have confirmed conflicts with me and will take the

exam thenexam then.

– You must have permission from me to take the exam at the alternate time.

• Alternate time: Wednesday May 4th, 12:40-2:40 pm• Location: BPS 1308

Final :

Y ll d th 8 5 11 h t f t• You are allowed three 8.5x11 sheets of notes. • Bring your notes, calculator and pencil to the exam in E1Vet Med.• You will have two hours to complete the exam.• There is no corrections set.

Review

Th l ti f bl i l d d i thi i fl t th• The selection of problems included in this review reflect mainly the material covered since the last midterm. Because we had no midterm on this material there is an added emphasis on it.

Ab t 40% f th i th t i l– About 40% of the exam is on the new material– About 60% of the exam on the material of the first two midterms.

• Among the final review problems, for example, there are little or no:– Two dimensional kinematics problems. – Velocity addition problems– Energy or power problemsEnergy or power problems– =I rotational dynamics problems:– Buoyancy problems.

T d t l f th fi l ill h t i th• To prepare adequately for the final, you will have to review the material covered on the first two midterms by studying the review problems distributed for the first two midterms, and your loncapaproblemsproblems.

Review Strategy

I ill l t f ld i bl f th t I di t ib t d d• I will select a few older review problems from the set I distributed, do them and then spend the rest of time on the new material. The solutions will be posted and will be numbered according to the number that appears on the problemthat appears on the problem.

50 A t li i th iti di ti h f f50. A wave traveling in the positive x direction has a frequency of 25.0 Hz as in the figure below. Find the amplitude (A), wavelength (), period (T), and speed (v) of the wave. Choose the correct values for A T and v from the options below:the correct values for A, ,T and v from the options below:a) 9 cm, 20 cm, 0.04 s, 500 cm/sb) 18 cm, 20 cm, 0.08 s, 500 cm/sc) 9 cm, 10 cm, 0.04 s, 250 cm/sd)18 cm, 10 cm, 0.04s, 250 cm/s

A 18cm / 2 9cm A 18cm / 2 9cm

T = 1/f =1/25 s = 0.04 s

10cm 2 20cm

v f 20cm 25Hz 500cm / s

48 A i i d d f th ili Wh 1 k i• 48. A spring is suspended from the ceiling. When a 1-kg mass is hung at the bottom, the spring stretches by 9.8 x 10-4 m. When the 1-kg mass is pulled further down and let go, it oscillates up and down on the spring What is its frequency of oscillation?the spring. What is its frequency of oscillation?1) 2 Hz 6) 12 Hz2) 4 Hz 7) 14 Hz3) 6 Hz 8) 16 Hz4) 8 Hz 9) 18 Hz5) 10 Hz 10) 20 Hz) )

51 A h t i ti b t h t i t 500 K d ld51. A heat engine operating between a hot reservoir at 500 K and a cold reservoir at 200 K has an efficiency that is 70% of its maximum possible value. If it receives lx106 J heat energy from the hot reservoir in 25 minutes it can do a quantity of work equal toin 25 minutes, it can do a quantity of work equal to – a)6.3x105J.– b)4.2x105J. c

max carnotT

a) e e 1T

2001 0.6500

– c)3.lxl05J.– d)2.5x105J.– e)1.7x105J.

hT 500

maxe 0.7e 0.7(0.6) .42 )

h

WeQ

6 5hW e Q .42 1x10 J 4.2x10 J

47 A i t d d th iddl A t (440• 47. An organ pipe, open at one end, produces the middle A note (440 Hz) when sustaining a standing wave at its third harmonic. What is the length of the pipe?1) 0 22 6) 1 07• 1) 0.22 m 6) 1.07 m2) 0.37 m 7) 1.62 m3) 0.58 m 8) 2.56 m4) 0.78 m 9) 3.19 m5) 0.97 m 10) 5.22 m

45 A h f f 60 H d d f 120 / Wh t• 45. A wave has a frequency of 60 Hz and a speed of 120 m/s. What are its period and wavelength?1) 60 s, 2.0 m 6) 0.017 s, 0.50 m2) 60 s, 0.50 m 7) 0.017 s, 2.0 m3) 2.0 s, 5.0 m 8) 7,200 s, 0.0083 m4) 2.0 s, 6.0 m 9) 7,200 s, 60 m) )5) 0.083 s, 16 m 10) 0.083 s, 6.0 m

Remainder of the problems

Th t i ll th t i i d I ill d f th t ti• That is all that is organized. I will do as many of the rest as time allows. Note that the preceding problems appear again in the following set. If you want to match your solutions against the posted solutions, the following order is the same as on the posted solutions setthe following order is the same as on the posted solutions set.

P (kPa)

V (m3)V (m )

• 44. If two people talk simultaneously and each creates an intensity p p y ylevel of 45 dB at a certain point, what is the total intensity level at this point?1) 46 dB 6) 65 dB) )2) 48 dB 7) 70 dB3) 51 dB 8) 80 dB4) 55 dB 9) 90 dB4) 55 dB 9) 90 dB5) 60 dB 10) 100 dB

45 A h f f 60 H d d f 120 / Wh t• 45. A wave has a frequency of 60 Hz and a speed of 120 m/s. What are its period and wavelength?1) 60 s, 2.0 m 6) 0.017 s, 0.50 m2) 60 s, 0.50 m 7) 0.017 s, 2.0 m3) 2.0 s, 5.0 m 8) 7,200 s, 0.0083 m4) 2.0 s, 6.0 m 9) 7,200 s, 60 m) )5) 0.083 s, 16 m 10) 0.083 s, 6.0 m

46 O f th t i h f d t l f f 262 H46. One of the notes on a piano has a fundamental frequency of 262 Hz and is produced by a wire that has a length of 0.69 m. The speed of sound in air is 343 m/s. Determine the ratio of the wavelength of the sound wave to the wavelength of the waves that travel on the wiresound wave to the wavelength of the waves that travel on the wire.1) 0.14 6) 2.82) 0.22 7) 3.53) 0.58 8) 4.14) 0.95 9) 6.95) 1.7 10) 8.0) )

47 A i t d d th iddl A t (440• 47. An organ pipe, open at one end, produces the middle A note (440 Hz) when sustaining a standing wave at its third harmonic. What is the length of the pipe?1) 0 22 6) 1 07• 1) 0.22 m 6) 1.07 m2) 0.37 m 7) 1.62 m3) 0.58 m 8) 2.56 m4) 0.78 m 9) 3.19 m5) 0.97 m 10) 5.22 m

48 A i i d d f th ili Wh 1 k i• 48. A spring is suspended from the ceiling. When a 1-kg mass is hung at the bottom, the spring stretches by 9.8 x 10-4 m. When the 1-kg mass is pulled further down and let go, it oscillates up and down on the spring What is its frequency of oscillation?the spring. What is its frequency of oscillation?1) 2 Hz 6) 12 Hz2) 4 Hz 7) 14 Hz3) 6 Hz 8) 16 Hz4) 8 Hz 9) 18 Hz5) 10 Hz 10) 20 Hz) )

49 Li ht f th h th th ith i t it f 1 360• 49. Light from the sun reaches the earth with an intensity of 1,360 W/m2. The planet Jupiter is 5.2 times as far from the sun as is earth. With what intensity does sunlight reach Jupiter?1) 0 75 W/ 2 6) 25 W/ 21) 0.75 W/m2 6) 25 W/m22) 1.5 W/m2 7) 50 W/m23) 3.0 W/m2 8) 100 W/m24) 6.0 W/m2 9) 200 W/m25) 12 W/m2 10) 400 W/m2

50 A t li i th iti di ti h f f50. A wave traveling in the positive x direction has a frequency of 25.0 Hz as in the figure below. Find the amplitude (A), wavelength (), period (T), and speed (v) of the wave. Choose the correct values for A T and v from the options below:the correct values for A, ,T and v from the options below:a) 9 cm, 20 cm, 0.04 s, 500 cm/sb) 18 cm, 20 cm, 0.08 s, 500 cm/sc) 9 cm, 10 cm, 0.04 s, 250 cm/sd)18 cm, 10 cm, 0.04s, 250 cm/s

A 18cm / 2 9cm A 18cm / 2 9cm

T = 1/f =1/25 s = 0.04 s

10cm 2 20cm

v f 20cm 25Hz 500cm / s

51 A h t i ti b t h t i t 500 K d ld51. A heat engine operating between a hot reservoir at 500 K and a cold reservoir at 200 K has an efficiency that is 70% of its maximum possible value. If it receives lx106 J heat energy from the hot reservoir in 25 minutes it can do a quantity of work equal toin 25 minutes, it can do a quantity of work equal to – a)6.3x105J.– b)4.2x105J. c

max carnotTa) e e 1T

2001 0.6500

– c)3.lxl05J.– d)2.5x105J.– e)1.7x105J.

hT 500

maxe 0.7e 0.7(0.6) .42 )

h

WeQ

6 5hW e Q .42 1x10 J 4.2x10 J

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