Q1. The displacement of a string carrying a traveling sinusoidal wave is given by:

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1 Coordinator: A. Mekki Saturday, Noveber, 008 Page: 1 Q1. The displaceent of a string carrying a traveling sinusoidal wave is given by: y( x, t) = y sin( kx ω t + ϕ). At tie t = 0 the point at x = 0 has a displaceent of zero and is oving in the positive y direction. Find the value of the phase constant φ. A) 180 degrees B) 90 degrees C) 135 degrees D) 0 degrees E) 70 degrees Q. A stretched string of ass.0 g and length 10 c, carries a wave having the following displaceent wave: y( x, t) = 0.05sin(π x 400 π t), where x and y are in eters and t is in seconds. What is the tension in the string? A) 800 N B) 150 N C) 55 N D) 15 N E) 100 N Q3. A haronic wave in a string is described by the equation: yxt (, ) = 0.00 sin( π x 40.0 t), where x and y are in and t in s. If the ass per unit length of this string is 15.0 g/, deterine the power transitted to the wave. A) 6.11 W B) 14.6 W C) 9.80 W D) 73.5 W E) 0 W Q4. Two identical traveling waves of aplitude 10.0 c, oving in the sae direction, are out of phase by π/4 rad. Find the aplitude of the resultant wave. A) 18.5 c B) c C) 1.0 c D) c E).40 c Q5.

2 Coordinator: A. Mekki Saturday, Noveber, 008 Page: A pipe has two consecutive resonance frequencies of 600 Hz and 1000 Hz. One end of the pipe is closed. What is the fundaental frequency of the pipe? A) 00 Hz B) 500 Hz C) 400 Hz D) 700 Hz E) 1600 Hz Q6. The intensity of sound eitted by a source is doubled. What is the change in intensity level of the sound? A) 3.0 db B).0 db C) 1.0 db D) 4.0 db E) 5.0 db Q7. Two identical loudspeakers, facing each other, are in phase and each has a frequency of 85 Hz. A an at the idpoint between the two loudspeakers oves slowly toward one of the until he hears the first iniu in sound. How far did he ove? (The speed of sound in air = 340 /s) A) 1.0 B).0 C) 4.0 D) 0.50 E) 0.5 Q8. If it were possible for a an to ove with the speed of sound directly toward a stationary whistle eitting a sound of frequency f, he would hear A) a sound of frequency f B) a sound of frequency f / C) no sound ( zero frequency) D) a sound of infinite frequency E) a sound of the sae frequency f Q9. The volue of 1.00 kg water is at a teperature of 10.0 C and at teperature of C. Calculate coefficient of volue expansion for water in that range of teperature.

3 Coordinator: A. Mekki Saturday, Noveber, 008 Page: 3 A) / C B) / C C) / C D) / C E) / C Q10. An isolated rod is in theral contact with hot reservoir at one end and with cold reservoir at other end ( Fig. 1). The rod consists of a 1.00 section of copper joined by a section of length L of steel. Both rods have the sae cross section area of 4.00 c. The teperature of copper-steel junction Tj is 65 C. Find L. ( k steel = 14 W/.K; k cu = 401 W/.K) Fig# T j = 65 C Hot reservoir 100 C Copper Steel Cold reservoir 0 C 1 L A) B) 0.80 C) 0.74 D) E) 0.54 Q11. How uch ice at -0.0 C ust be ixed with 0.5 kg of water, initially at 0.0 C to obtain a final teperature of ixture of 0.0 C with all ice elted. (c ice = 0 J/kg K) A) 56 g B) 95 g C) 15 g D) 88 g E) 30 g Q1. A gas expands fro a volue of.00 3 to a volue of along two different paths as shown in Fig. The heat added to the gas along path IAF equals J. Find the heat added during path IF. Fig#

4 Coordinator: A. Mekki Saturday, Noveber, 008 Page: 4 P(x 10 5 N/ ).00 A 1.00 I F V( 3 ) A) J B) J C) J D) J E) J Q13. Fig. 3. shows a cycle undergone by 1.0 ol of a onatoic ideal gas. What is the heat added to the gas during the whole cycle? Fig# A) 50 J B) 3700 J C) -300 J D) 0.0 J

5 Coordinator: A. Mekki Saturday, Noveber, 008 Page: 5 E) 760 J Q14. What is the change in the internal energy of a 1.00 ole of a onatoic ideal gas that goes fro point 1 (T1= 455K and pressure P1 = 1.00 at) to point (T = 300 K and pressure P = 1.00 at.)? A) J B) -30 J C) 50 J D) J E) 0 J Q15. The ass of an oxygen olecule is 16 ties that of a hydrogen olecule. At roo teperature, the ratio of the rs speed of an oxygen olecule to that of a hydrogen olecule is: A) 1/4 B) 16 C) 1/16 D) 1 E) 4 Q16. A 0.85 ol of an ideal gas undergoes an isotheral process. The initial volue is and the final volue is If the heat added to the gas is 1000 J, find the teperature of the gas. A) 360 K B) 300 K C) 600 K D) 150 K E) 180 K Q17. The efficiency of a car engine is 0% when the engine does 1. kj of work per cycle. What is the energy Q L the engine loses per cycle as heat? A) 4.8 kj B) 1. kj C) 6.1 kj D) 3.1 kj E) 7.0 kj

6 Coordinator: A. Mekki Saturday, Noveber, 008 Page: 6 Q18. The freezing copartent of a Carnot refrigerator is at 69 K while outside air in the roo is at 98 K. If the power of refrigerator otor is 150 W, what is axiu aount of energy that can be extracted as heat fro the freezing copartent in 10.0 in? A) J B) J C) J D) J E) J Q19. Calculate the change in entropy of 1.0 kg of ice at 0.0 C when its teperature is increased to 0.0 C [ L fusion-ice = 333 kj/kg; c water = 4190 J/kg.K] A) J/K B) J/K C) J/K D) J/K E) J/K Q0. A 5.00 ol saple of an ideal gas expands reversibly and isotherally at 355 K until its volue doubled. What is the change in entropy of the gas? A) 8.8 J/K B) 80.0 J/K C) 11.0 J/K D) 70.5 J/K E) 50.9 J/K

7 Physics 10 Major1 Forula sheet v v ω = λf = k τ = µ v = B ρ y = ysin(kx ± ωt + φ) 1 P = µω y v S = S cos( kx ω t ) P = P sin( kx ωt); where P = ρ vωs I = 1 ρ ( ω S ) v I β = 10 log, I o = 10-1 W/ I o Power I = Area f v vd = f ± v± vs φ φ y = y cos sin kx ωt + y = (y sinkx) cosωt nv f n =, L n = 1,,3,... nv f n =, 4L n = 1,3,5... L = αl T V = β V T PV = nrt = NkT L = λ π φ L = λ = 0,1,,. 1 L = + λ, = 0,1,,.. γ γ 1 PV = constant; TV = constant 3 C = R for onatoic gases, v 5 = R for diatoic gases. 9 T F = T C Q = L Q = c T Q = nc T E int = Q W E int = nc V T C p - C v = R W = PdV Q TH -TC Pcond = = ka t L v ( 3/)kT =, v rs = 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: 3RT M 1 Liter = R = 8.31 J/ol K N A = 6.0 x 10 3 olecules/ole 1 at = 1.01 x 10 5 N/ k = 1.38 x 10-3 J/K 1 calorie = Joule g = 9.8 /s for water: J J cw = 4190 ; cice = 0 kg.k kg. K 5 J 6 J LF = , LV = kg kg