Sec# Wave Motion - Superposition and Interference of Waves Grade# 50

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1 Coordinator: Dr. A. Naqvi Saturday, August 0, 009 Page: Q. The function y(x,t) = 5.0 cos (x- 0 t) with x and y in meters and t in seconds, describes a wave on a taut string. What is the mass of one meter of the string if the tension in the string is 40.0 N? A) 00 g B) 00 g C) 0 g D) 0 g E) 50 g Sec# Wave Motion - The Seed of Waves on Strings Q. What hase difference ( in wavelength ) between two identical traveling waves, moving in the same direction along a stretched string, results in the combined wave having an amlitude.75 times that of the common amlitude of the two combined waves? A) 0.6 B).30 C).80 D).0 E) 0.89 Sec# Wave Motion - Suerosition and Interference of Waves Q3. What is the third lowest frequency for standing waves on a 0.0 m long wire with.0 g mass and stretched under a tension of 00 N? A) 50 Hz B) 85 Hz C) 50 Hz D) 50 Hz E) 00 Hz Sec# Wave Motion - Standing Waves and Resonance Q4. Energy is transmitted at the rate of P 0 by a wave of frequency f 0 on a string under tension 0. What is the new energy transmission rate P in terms of P 0 if the tension is increased to 4 0 and frequency is decreased to f 0 /? A) P= P 0 / B) P=4 P 0 c--n-0-s-0-e--fg--fo-0

2 Coordinator: Dr. A. Naqvi Saturday, August 0, 009 Page: C) P= P 0 D) P= P 0 /4 E) P= P 0 Sec# Wave Motion - Energy and Power Transmitted by Sinusoidal Waves on Strings Q5. What is the bulk modulus of nitrogen gas if the seed of sound in nitrogen is 30 m/s. Assume 8.0 g of nitrogen occuies.4 L volume? A).0x 0 5 N/m B) 3.84 x 0 5 N/m C).0 x 0 6 N/m D).0 x 0 3 N/m E) 3.84 x 0 4 N/m Sec# Sound Waves - Seed of Sound Waves Q6. The form of a sound wave travelling through air is S(x,t) = S m cos (kx+3000t+), where x is in meters and t in seconds. What is the shortest time interval that any air molecule takes along the ath to move between dislacements S = +S m /3 and S = - S m /3? A) 0.3 ms B) 0.4 ms C). ms D) 0.89 ms E) 5.3 ms Sec# Sound Waves - Seed of Sound Waves Q7. A ie, filled with air, is closed at one end. If the third lowest harmonic frequency of the ie is 750 Hz, what is the fundamental frequency for the ie? A) 50 Hz B) 50 Hz C) 75 Hz D) 375 Hz E) 75 Hz Sec# Sound Waves - Standing waves in Air Columns Q8. c--n-0-s-0-e--fg--fo-0

3 Coordinator: Dr. A. Naqvi Saturday, August 0, 009 Page: 3 A train aroaches a mountain at a seed of.0 m/s. The train engineer sounds a whistle that emits a frequency of 40 Hz. What will be the sound frequency that the engineer hears reflected off the mountain? ( seed of sound =340 m/s) A) 475 Hz B) 550 Hz C) 350 Hz D) 40 Hz E) 385 Hz Sec# Sound Waves - Doler Effect Q9. The outside temerature changes by 40 F during a day. What is this temerature change on the Kelvin scale? A) K B) 86 K C) 7 K D) 0 K E) 95 K Sec# Temerature - Termometers and Temerature Scale Q0. A bolt hole in a brass late has a diameter of.00 cm at 0.00 C. What is the diameter of the hole when the late is heated to 0.0 C? (The coefficient of linear thermal exansion for brass is /C ). A).05 cm B).5 cm C).495 cm D).300 cm E).550 cm Sec# Temerature - Thermal Exantion of Solids and Liquids Q. 00 g of ice at 0 C is droed into a calorimeter of negligible heat caacity containing 350 g of water at 0 C. What is the final temerature of the system when it reaches equilibrium? A) 0 C B) 4 C C) -3 C D) 3 C E) -4 C c--n-0-s-0-e--fg--fo-0

4 Coordinator: Dr. A. Naqvi Saturday, August 0, 009 Page: 4 Sec# Heat and the First Law of Thermodynamics - Latent Heat Q. What is the outside temerature if 6.8 x 0 6 J of heat is lost through a 4.0 m area of 0.30 cm thick window glass in one hour from a house ket at 0 C (Thermal conductivity of window glass k = 0.84 W/m.K) A) 6 C B) 4 C C) 0 C D) 8 C E) 4 C Sec# Heat and the First Law of Thermodynamics - Heat Transfer Q3. A quantity of an ideal gas is exanded to twice its initial volume. The rocess may be isothermal, isobaric or free exansion. Rank those three rocesses in order of the work done by the gas, Least to Greatest. A) Free exansion, isothermal, isobaric B) Isobaric, free exansion, isothermal C) Isothermal, isobaric, free exansion D) Isobaric, isothermal, free exansion E) Free exansion, isobaric, isothermal Sec# Heat and the First Law of Thermodynamics - The First Law of Thermodynamics Q4. PV diagram for 4.3 g samle of an ideal gas contained in a container is shown in Fig.. The temerature T of state is C. What is the temerature T 3 of state 3? A) -53 C B) 0 C C) 6 C D) -3 C E) 390 C Sec# The kinetic Theory of Gases - Molecular Model of an Ideal Gas Q5. There is mol of air molecules contained in a cylinder at an initial temerature of 300K. Then the air molecules are comressed adiabatically to /5 of its initial volume. How much work does the air do? (Take gamma=.40 and Cv = 0.8 J/mol.K). c--n-0-s-0-e--fg--fo-0

5 Coordinator: Dr. A. Naqvi Saturday, August 0, 009 Page: 5 A) 494 J B) +494 J C) 34 J D) +34 J E) 0 J Sec# The kinetic Theory of Gases - Adiabatic Processes for Ideal Gas Q6. The temerature of a gas is increased by 0 K. As result, the rms velocity of the molecules increases from 400 m/s to 480 m/s. The molecular mass of the gas, in g/mol, is: A) 39 B) 47 C) 45 D) 4 E) 43 Sec# The kinetic Theory of Gases - Molecular Model of an Ideal Gas Q7..0 kg of water freezes at 0 C. What is the change in entroy of water during this freezing rocess? A) J/K B) J/K C) J/K D) J/K E) J/K Sec# Heat engines, entroy and the nd law - Entroy Q8. A 3.47 mol samle of an ideal gas exands reversibly and isothermally at 400 K until its volume doubled. What is increase in entroy of the gas? A) 0.0 J/K B) 5.0 J/K C) 0.0 J/K D) 30.0 J/K E) 5.0 J/K Sec# Heat engines, entroy and the nd law - Entroy Q9. c--n-0-s-0-e--fg--fo-0

6 Coordinator: Dr. A. Naqvi Saturday, August 0, 009 Page: 6 Fig. shows a cycle for a heat engine for which Q H = 35 J. The thermal efficiency of the engine is : A) 9 % B) 4 % C) 3 % D) 57 % E) 9 % Sec# Heat engines, entroy and the nd law - Heat Engine, Pum and Refrigerators Q0. A heat um delivers heat to a room at the rate of 34 kj er second and maintains the room at a temerature of 93 K when the outside temerature is 9 K. The ower requirement for the heat um under these oerating conditions is : A) 7.4 k W B) 3 k W C) 6.0 k W D) 5 k W E) 5.6 k W Sec# Heat engines, entroy and the nd law - Heat Engine, Pum and Refrigerators Test Exected Average = 49 c--n-0-s-0-e--fg--fo-0

7 Phys0 First Major Code: Term: 083 Saturday, August 0, 009 Page: Figure V ( cm 3 ) Figure

8 Phys0 First Major Code: Term: 083 Saturday, August 0, 009 Page: 7 Physics 0 Major Formula sheet v v λf k v B y ymsin(kx ωt φ) P y m v S S m cos( kx t ) P P sin( kx t ); where P v S I S m m m m v I 0 log, I o = 0 - W/m I o Power I Area f v vd f v vs φ φ y y mcos sinkx ωt y (y sinkx) cosωt m nv f n, L n,,3,... nv f n, 4L n,3,5... ΔL αlδt ΔV VΔT PV nrt NkT ΔL λ π φ ΔL mλ m = 0,,,. ΔL m λ, m = 0,,,.. P V constant; TV constant 3 C = R for monatomic gases, v 5 = R for diatomic gases. T F Q ml 9 T 5 C 3 Q mct Q = nct Q W ΔE int ΔE int nc VΔT C - C v = R W PdV Q T Pcond k A t mv 3/kT, W = Q H Q L W Q L ε - Q Q H H H -T L QL K W Q L T L, Q T dq S T c H H Constants: Liter = 0-3 m 3 R = 8.3 J/mol K C v rms 3RT M N A = 6.0 x 0 3 molecules/mole atm =.0 x 0 5 N/m k =.38 x 0-3 J/K calorie = 4.87 Joule g = 9.8 m/s w L for water: F J J 490 ; cice 0 kg.k kg. K J 3.330, L.560 kg 5 6 V J kg

9 Phys0 First Major Code: Term: 083 Saturday, August 0, 009 Page: 8