Physics 2220 Fall 2012 Paolo Gondolo PLEASE FILL IN THE INFORMATION BELOW. Name (printed): Name (signed): Student ID Number.

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1 Physics 2220 Fall 2012 Paolo Gondolo EXAM 4 PLEASE FILL IN THE INFORMATION BELOW Name (printed): Name (signed): Student ID Number U Discussion Instructor: Chad Chris Peter

2 Physics 2220 Fall 2012 Paolo Gondolo Data: Use these constants (where it states, for example, 1 ft, the 1 is exact for significant figure purposes). 1 ft = 12 in (exact) 1 m = 3.28 ft 1 mile = 5280 ft (exact) 1 hour = 3600 sec = 60 min (exact) 1 day = 24 hr (exact) g earth = 9.80 m/s 2 = 32.2 ft/s 2 g moon = 1.67 m/s 2 = 5.48 ft/s 2 1 year = days 1 kg = slug 1 N = pound 1 horsepower = 550 ftpounds/s (exact) M earth = kg R earth = km M sun = kg R sun = m M moon = kg R moon = km G = Nm 2 /kg 2 k = Nm 2 /C 2 ε o = C 2 /(N m 2 ) e electron charge = C m electron = kg μ o = 4π 10-7 Tm/A (exact) N(Avogadro's No.) = atoms/gmmole = atoms/kgmole 1 Tesla = 10,000 gauss (exact) ρ(h 2 O) = 1000 kg/m 3 cos(a ± b) = cos a cos b a sin b sin(a ± b) = sin a cos b ± sin b m proton = kg h = J π = 3.14 c = m/s 3 1 x x a dx x a 3 dx x x a 3 a 2 x 2 a 2 ax 1 e dx e a ax xdx 1 3/ 2 x a x a xdx a x a x dx n x x a x a dx 1 a x a n x x a a x xdx x a x a dx 1x 1x sin, or cos a x a a dx 1 n a bx a bx b dx 1 2 a bx ba bx

3 Physics 2220 Fall 2009 Fall 2012 Paolo Gondolo Name: Unid: Discussion TA: 1 The figure shows voltage and current graphs for a capacitor. [11 pts.] What is the emf frequency f? [11 pts.] What is the value of the capacitance C? (c) [11 pts.] Draw the capacitor s voltage and current phasors at t = 7.5 ms. For each, specify the value of the phasor magnitude and of its angle with the x axis.

4 Physics 2220 Fall 2009 Fall 2012 Paolo Gondolo Name: Unid: Discussion TA: 2 A 3.0-cm-tall object is 9 cm in front of a converging lens that has an 18 cm focal length. (c) [12 pts.] Use ray tracing on the figure below to approximately draw the image. Do this as accurately as you can. [4 points for each ray, no credit for sloppy or extra rays.] [10 pts.] Is the image real or virtual? Upright or inverted? [12 pts.] Using appropriate formulas, calculate the image position and height.

5 Physics Fall 2009 Fall 2012 Paolo Gondolo Name: Unid: Discussion TA: 3 Photons from a helium-neon laser (wavelength 633 nm) pass through a 10-μm-wide slit and create a diffraction pattern on a screen 1.0 m behind the slit. (c) [11 pts.] What is the width of the central maximum on the screen? [11 pts.] If the photons are replaced by electrons, what wavelength must the electrons have to produce the same diffraction pattern on the screen? [11 pts.] What is the speed of such electrons?

6 Ph~sics Fall 2012 Paolo (;ondolo Name: s;'olla ±ion Unid: Discussion TA: --->."C,..t...:...l~"'-r-""\5""-- 1 The figure shows voltage and current graphs for a capacitor. [11 pts.) What is the emf frequency /? [11 pts.} What is the value ofthe capacitance C? (c) [11 pts.} Draw the capacitor's voltage and current phasors at t = 7.S ms. For each, specify the value of the phasor magnitude and of its angle with the x axis. /Voltage IOV 15 rna 0~-~---r~~L-~~ s 0.02 s I / r-15 rna -10 V1 Current fc) Cb) '"

7 Name: --~~==~ Unid: Discussion TA:,.- 2 A 3.0-cm tall object is 9 cm in front of a converging lens that has an 18 cm focal length. (c) [12 pts.] Use ray tracing on the figure below to approximately draw the image. Do this as accurately as you can. [4 pointsfor each ray, no credit for sloppy or extra rays.] [10 pts.] Is the image real or virtual? Upright orinverted?\};rio:;;.,l... upr;~t,+ [12 pts.] Using appropriate formulas, calculate the image position and height. - focal point object - ~.. ty\;' ~ - h:r ho - -

8 I'h}'sirs 220 Fnll2012 Paolo Gondolo Name 'PE:TCR P ~ONCJ~ Unid : Discussion TA: _ 3 Show "II work!! Report all numbers to three (3) significant figures. Photons from a helium-neon laser (wavelength 633 nm) pass through a 10-l1m-wide slit and create a diffraction pattern on a screen 1.0 m behind the slit. (c) [II pis'] What is the width of the central max imum on the screen? [I J pls'] If the photons are replaced by electrons, what wavelength must the electrons have to produce the same diffraction pattern on the screen? [J I pis'] What is the speed of such electrons? ' (Gt) First... j h i 10\...\0)'\. / a- r - Ic:, - - ) <t a /... ~ l.11t\/ ~ --/" -'" O,;~e.:: A.p (W z. ' 2 ~Me :: A - c:t. tan. e = (IJJ/2 L Tk:, I M =(2.L). ian &.. (2~) tan ( ~ I (,}) ] '" A t?l.) (C) ::) _31 j,. q, f/it/o d~ nr..:.. ~ 1./5" ID (»<./~ el -= ::-