Phys102 First Major-123 Zero Version Coordinator: xyz Sunday, June 30, 2013 Page: 1

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1 Coordinator: xyz Sunday, June 30, 013 Page: 1 Q1. A string has a ass of 0.0 g and a length of 1.6. A sinusoidal wave is travelling on this string, and is given by: y (x,t) = sin (0.30 x 80 t + 3π/) (SI units). What is the agnitude of the tension in the string? A) 8.9 N B) 3.3 N C) 4.7 N D) 9. N E) 5.4 N Sec# Wave - I - The speed of a Traveling Wave Grade# 58 Q. The average power transitted by a sinusoidal wave on a stretched string does not depend on A) the length of the string. B) the frequency of the wave. C) the wavelength of the wave. D) the tension in the string. E) the aplitude of the wave. Sec# Wave - I - Energy and Power of a Traveling String Wave Grade# 53 Q3. A standing wave is established on a 3.0 long string fixed at both ends. The string vibrates in three loops with an aplitude of 1.0 c. If the wave speed is 100 /s, what is the frequency? A) 50 Hz B) 100 Hz C) 33 Hz D) 5 Hz E) 10 Hz Sec# Wave - I - Standing Waves and Resonance Grade# 58 Q4. A string of length.5 is fixed at both ends. A standing wave of frequency 100 Hz is set up on the string. The distance between two adjacent nodes is What is the fundaental frequency of the string? A) 0 Hz B) 100 Hz C) 40 Hz D) 500 Hz E) 60 Hz

2 Coordinator: xyz Sunday, June 30, 013 Page: Sec# Wave - I - Standing Waves Grade# 53 Q5. Two speakers, facing each other and separated by a distance of 5.00, are driven by the sae oscillator, as shown in Figure 1. A listener starts walking fro the left speaker toward the right one, along the line joining the. He hears the fist iniu at x = Find the frequency of the oscillator. Speed of sound = 343 /s. A) 57. Hz B) 114 Hz C) 4.9 Hz D) 85.8 Hz E) 34.3 Hz Sec# Wave - II - Interference Q6. A point source uniforly eits 440 W of sound in all directions. How far fro the source will the sound level be 106 db? A) 9.7 B) 1.8 C) 3.5 D) 38.1 E) 5.5 Sec# Wave - II - Intensity and Sound Level Q7. A train approaches a ountain at a speed of 0.8 /s. The train s engineer sounds a whistle that eits sound with a frequency of 40 Hz. What will be the frequency of the sound reflected fro the ountain, as heard by the engineer? Speed of sound = 343 /s. A) 474 Hz B) 430 Hz C) 446 Hz D) 40 Hz E) 400 Hz

3 Coordinator: xyz Sunday, June 30, 013 Page: 3 Sec# Wave - II - The Doppler Effect Grade# 43 Q8. Tube A has length L A and is open at both ends. Tube B has length L B and is closed at one end. If the fundaental frequencies of the two tubes atch then: A) L B = L A / B) LB = LA C) LB = L A /4 D) LB = LA E) LB = 4 L A Sec# Wave - II - Source of Musical Sound Grade# 55 Q9. A bridge is ade of segents of concrete, each of length L = 50, that are placed end to end. Every two adjacent segents are separated by a spacing ΔL to allow for theral expansion, without the two segents touching. If the teperature changes by 150 F o, what should be the iniu value of ΔL? The coefficient of linear expansion of concrete is ( o C) -1. A) 5.0 c B) 7.5 c C) 10 c D).5 c E) 9.5 c Sec# Teerature, Heat, and the First Law of Therodynaics - Theral Expansion Grade# 58 Q10. A 4.0 kg block of ice at 0.0 o C is ixed with 4.0 kg of stea at 100 o C. What is the final equilibriu teperature of the syste? A) 100 o C o B) 0.0 C o C) 50 C o D) 85 C E) o C Sec# Teerature, Heat, and the First Law of Therodynaics - The Absorption of Heat by Solids and Liquids Q11. Two rods, ade of different aterials but having the sae length and diaeter, are welded end to end between two theral reservoirs, as shown in Figure 3. In steady state, what is the teperature (T x ) at the junction between the two rods?

4 Coordinator: xyz Sunday, June 30, 013 Page: 4 A) 100 k 1 /( k 1 + k ) B) 100 k/( k 1 + k ) C) 100 k1 k /( k 1 + k ) D) 50 k1/( k 1 + k ) E) 50 k/( k 1 + k ) Sec# Teerature, Heat, and the First Law of Therodynaics - Heat Transfer Mechaniss Grade# 50 Q1. An ideal gas undergoes the cyclic process shown in Figure. What are the signs of the heats Q AB, Q BC, Q CA, respectively? A) positive, negative, negative B) positive, negative, positive C) positive, positive, negative D) negative, positive, positive E) negative, positive, negative Sec# Teerature, Heat, and the First Law of Therodynaics - The First Law of Therodynaics Grade# 45 Q13. Two oles of a onatoic ideal gas are initially at 7.0 o C and occupy a volue of 0.0 L. The gas is expanded at constant pressure until the volue is doubled. Find the change in the internal energy of the gas. A) 7.48 kj B) 1.5 kj C) kj

5 Coordinator: xyz Sunday, June 30, 013 Page: 5 D) 1.1 kj E) 5.44 kj Sec# The kinetic Theory of Gases - The Molar Specific Heats of an Ideal Gas Q14. An ideal diatoic gas, initially at 0.0 o C, is copressed adiabatically fro 1.00 L to L. What is the final teperature of the gas? A) 387 K B) 99 K C) 465 K D) 305 K E) 117 K Sec# The kinetic Theory of Gases - The Adiabatic Expansion of an Ideal Gas Grade# 53 Q15. The speeds of four particles are as follows: v 1 = 1.0 /s, v =.0 /s, v 3 = 3.0 /s and v4 = 4.0 /s. What is their root ean square speed? A).7 /s B).5 /s C) 1.9 /s D) 5.5 /s E) 3. /s Sec# The kinetic Theory of Gases - Pressure, Teperature and RMS Speed Grade# 43 Q16. Figure 4 shows a cycle consisting of five paths: AB is isotheral at 300 K, BC is adiabatic with work = 8.0 J, CD is isobaric at 5.0 at, DE is isotheral, and EA is adiabatic with a change of internal energy of 10 J. What is the change in the internal energy of the gas along path CD? A).0 J B) +.0 J

6 Coordinator: xyz Sunday, June 30, 013 Page: 6 C) 1 J D) + 1 J E) 18 J Sec# The kinetic Theory of Gases - Translational Kinetic Energy Q17. A real heat engine is represented by the diagra shown in Figure 5. The heat expelled to the low-teperature reservoir can be A) 60 J B) 40 J C) 0 J D) 10 J E) zero Sec# Entropy and the Second Law of Therodynaics - Entropy in the Real World: Engines Grade# 43 Q18. Point i in Figure 6 represents the initial state of an ideal gas at teperature T. Rank the entropy changes that the gas undergoes as it oves reversibly fro point i to points a, b, c, and d, greatest first.

7 Coordinator: xyz Sunday, June 30, 013 Page: 7 A) b, a, c, d B) a, b, c, d C) b, d, a, c D) (b and d tie), (a and c tie) E) (b and d tie), a, c Sec# Entropy and the Second Law of Therodynaics - Change in Entropy Grade# 45 Q19. In an experient, 00 g of aluinu at 100 o C is ixed with 00 g of water at 0 o C. The final equilibriu teperature is 34 o C. What is the change in entropy of the aluinu-water syste? The specific heat of aluinu is 900 J/kg.K. A) J/K B) + 74 J/K C) 74 J/K D) 4.1 J/K E) zero Sec# Entropy and the Second Law of Therodynaics - Change in Entropy Grade# 50 Q0. A Carnot refrigerator operates between two reservoirs at 3.0 o C and 7 o C. How long should the refrigerator be operated, with a 500 W power input, in order for it to absorb 4500 J of heat fro the cold reservoir? A) 1.0 s B) 5.0 s C).7 s D) 6.3 s E) 1.6 s Sec# Entropy and the Second Law of Therodynaics - Entropy in the Real World: Refrigerators Grade# 53 Test Expected Average = 50

8 v = τ µ v = B ρ y = y sin(kx 1 P = µω y ωt) v S = S cos( kx ωt) P = P sin(kx ωt) P = ρvω S I = ½ ρ (ωs ) v I β = 10log I o P s I = 4πr v ± v D f = f v vs y = y cos(φ/) sin(kx ωt + φ/) y = y sinkx cosωt nv f n =, n = 1,,3,... L nv f n =, n = 1,3,5... 4L λ ΔL = φ π ΔL = λ = 0,1,,. 1 ΔL = + λ, = 0,1,,. T c = T 73 9 T F = T + 3 C 5 ΔL = αlδt V = βv T PV = nrt = NkT γ PV = constant γ 1 TV = constant Q = L Q = c T Q = n C V T Q = n CP T ΔE int = Q W ΔE int = nc VΔT C p - C v = R W = PdV W = nrt ln(v f /V i ) P cond = v = Q t = ka(t ( 3/)kT H L T 3RT v rs = M W = Q H Q L W Q L ε = = 1- Q H Q H QL K = W Q L T = L, = Q T dq S T H H Constants: 1 Liter = at = 1.01 x 10 5 N/ R = 8.31 J/ol K N A = 6.0 x 10 3 olecules/ole -3 k = 1.38 x 10 J/K Io = 10-1 W/ For water: c = 4190 J/kg.K L F = 333 kj/k LV = 56 kj/k C )