Physics 1C. Class Review. "All good things must come to an end. --Proverb

Transcription

1 Physics 1C Class Review "All good things must come to an end. --Proverb

2 1) Simple Harmonic Motion: For a mass on a spring, the force on the mass will be given by: In general, anything that exhibited simple harmonic motion: r F = F r restoring = ( constant) ( displacement) The periods of SHM can be: T spring = 2π m k T pend = 2π L g

3 2) Waves: Waves were a disturbance in a medium created by a source. We represent a traveling wave with a sine wave. We could relate wavelength and frequency by: v wave = λ T = λf

4 3) Sound: Sound waves are longitudinal waves traveling through a medium. The intensity level, β, of sound is: β = ( 10dB)log I When the source or the observer is moving, the frequency will change: I o v f o = f sound ± v o s v sound m v s Standing waves occur under wave reflection such that nodes and anti-nodes are created:

5 4) Reflection and Refraction: When light is reflected off of a surface it will be reflected at an angle given by: θ 1 = ʹ θ 1 When light moves between two different media, the light will be refracted at an angle given by: n 1 sinθ 1 = n 2 sinθ 2 Remember that all angles are measured with respect to the normal!

6 5) Mirrors and Lenses: Mirrors use the reflection of light to divert the light rays. 1 p + 1 q = 1 f M = ʹ h h = q p Lenses use the refraction of light to divert the light rays. Ray diagrams may be useful:

7 6) Wave Interference: The wave nature of light leads to interference effects. This can be caused by a path length difference or a phase shift. Double slit interference was due to a path length difference. δ = mλ = d sinθ Thin film interference was due to both: Con. for 1 phase change Des. for 1 phase change 2nt = ( m + 1 2)λ For m = 0, 1, 2...

8 7) The Eye and Optical Instruments: The eye uses a converging lens to produce a sharp, real image. The eye can focus on objects at different distances by varying the shape of the lens. A converging lens can act as a simple magnifier. A microscope uses two lenses to greatly magnify a small object. A telescope can use either reflection or refraction to view the object (it needs at least two optical systems).

9 8) Quantum Physics: Light exhibits wave-particle duality. Experiments such as the photoelectric effect and the Compton effect demonstrate the particle nature of light. Experiments like double-slit interference and Bragg s X-ray scattering demonstrate the wave nature of light. Light is also quantized into discrete units known as photons. debroglie hypothesized that all matter also could have wave properties. E n = nhf λ = h p = h mv

10 9) Atomic Physics: 1 λ Emission spectra were always at particular wavelengths for certain elements. = R H 1 2 nf 1 n 2 i Bohr took this information and decided the atom must be quantized (just about everything in it was). r n = n 2 h 2 E m e k e e 2 tot = 1 2 k e ev e = n 2 a o n 2 Quantum mechanics starts with the principle quantum number, n, but also includes other quantum numbers (l, m s ).

11 10) Nuclear Physics: Rutherford s thin-foil experiment demonstrated that the nucleus is small and dense. Stable nuclei can be categorized by the amount of binding energy per nucleon they have. Q = ( Δm)c 2 = ( m initial m final )c 2 There are three types of radioactivity: alpha, beta, and gamma. They decay via: N = N o e λt

12 Clicker Question CR-1 In a single-slit diffraction experiment, as the width of the slit is made smaller, the width of the central maximum of the diffraction pattern: A) becomes smaller. B) becomes wider. C) remains the same. D) There will be no diffraction pattern on the screen since the apparatus and screen distance are set up for a particular width.

13 Finals Week Information Clicker points (along with the other scores) will be put on-line by Tuesday morning. If you have issues with the clicker points then bring them up either at the office hour or the final. Make sure that you have attempted to calculate the correct value before you bring up the issue with me. Recall that clicker points are awarded by answering questions (1 pt per question) and by answering correctly (1 pt per question). So there are two possible points per clicker question.

14 ALMOST THE END Final is Thursday, 11:30am - 2:30pm in this room (2622 York). Quizzes, HW, Lecture examples, Clicker? s, Book examples, Odd nonassigned HW problems... Bring a Scantron, your ID and write your proper quiz code number on your form. For the most part, every chapter will be equally represented on the final. Tuesday I will be at 109 Pepper Canyon Hall from 5pm-6:30pm (also Wednesday OH 3pm - 4pm in my office).

15 THE END "Go forth and slay dragons. --Roderick Reid