精華區beta NTU-Exam 關於我們 聯絡資訊
課程名稱︰普通物理甲上 課程性質︰系定必修 課程教師︰趙治宇 開課學院:工學院 開課系所︰化工系 考試日期(年月日)︰97.01.17 考試時限(分鐘):180分鐘 是否需發放獎勵金:是 (如未明確表示,則不予發放) 試題 : Final Exam Instructor: CY Chao 1.When n moles of an ideal gas doubles its volume in a free expansion. Derive the entropy change is nRln2 using (1)thermodynamics and (2)statistical mechanics.(5%,5%) 2.Derive the gravitational force at a point P, a distance z from a disk along its central axis. This disk is uniform, and radius R and total mass M.(8%) (The mass of the point is m) 3.Three waves y(x,t)1,y(x,t)2, and y(x,t)3 have the same wavelength and travel in the same direction along a string. Their amplitudes are ym1=4.0mm, ym2=3.0mm , and ym3=5.0mm, and their phase constant are 0, π/3, and π/2 rad, respectively. What are the amplitude y'm and phase constant β of the result wave?(4%,4%) 4.Describe (a)the evidence of the universe expansion. (b)the working principle of laser cold trapping invented by Prof. Steven Chu.(2%,4%) 5.(a)Describe the working principle of a strain gauge for small strain measurements. (b)Design an experiment to accurately measure the moment inertia of any-shaped object.(4%,4%) 6.Two cylinders with radii R1 and R2 and rotational inertias I1 and I2 about the central axis are supported by axes perpendicular to plane of Fig.1. The large cylinder is initially rotating with angular velocity ω0. The small cylinder is moved to the right until it touches the large cylinder and is caused to rotate by the frictional force between the two. Eventually, slipping ceases, and the two cylinders rotate at constant rates in the opposite directions. Find the final angular velocity ω2 of small cylinder in terms of I1, I2, R1, R2, and ω0.(10%) 7.A bowler throws a bowling ball of radius R=11cm along a lane. The ball(Fig.1) slides on the lane with initial Vcom,0=8.5m/s and initial angular speed ω0=0. The coefficient of kinetic friction between the ball and the lane is 0.21. The kinetic frictional force fk acting on the ball causes a linear acceleration of the ball while producing a torque that causes an angular acceleration of the ball. When speed Vcom has decreased enough and angular speed ω has increased enough, the ball stop sliding and then rolls smoothly. (a)How long does the ball slide? (b)How far does the ball slides? (c)What is the linear speed of the ball when smooth rolling begins?(3%,3%,4%) 8.In Fig.2, a solid cylinder attached to a horizontal spring(k=3.00N/m) rolls without slipping along a horizontal surface. If the system is released from rest when the spring is stretched by 0.250m, find the period of this simple harmonic motion under these conditions.(8%) 9.The p-V diagram in Fig.3 shows two paths along which a sample of gas can be taken from state a to state b, where Vb=3V1. Path 1 requires that energy equal to 5.0p1V1 be transferred to the gas as heat. Path 2 requires that energy equal to 5.5P1V1 be transferred to the gas as heat. What is the ratio p2/p1?(6%) 10.(a)For an ideal gas, prove that the relation between the pressure and volume during an adiabatic process is PV^γ=constant, where γ=Cp/Cv.(b)1 mol oxygen (O2) at initial pressure 2 atm undergoes an adiabatic expansion from an initial volume of 12L to a final volume of 19L. What is the work done by the gas during this volume change?(6%,4%) 11.In Fig.4, and aluminum wire, of length L1=60.0cm, cross-sectional area 1.00×10^-2cm^2, and density 2.60g/cm^3, is jointed to a steel wire, of density 7.80g/cm^3 and the same cross-sectional area. The compound wire, loaded with a block of mass m=10.0kg, is arranged so that the distance L2 from the joint to the supporting pulley is 86.6cm. Transverse waves are set up on the wire by an external source of variable frequency; a node is located at the pulley. (a)Find the lowest frequency that generates a standing wave having the joints one of the nodes. (b)How many nodes are observed at this frequency?(4&,4%) 12.A certain triple-star system consists of two stars, each of mass m, revolving in the same circular orbit of radius r around a central star of mass M(Fig.5). The two orbiting stars are always at opposite ends of a diameter of the orbit. Derive an expression for the period of revolution of the stars.(8%) P.S. All figures comes from Fundamentals of Physics Eight Edition Fig.1 of No.6 P.271 FIG. 10-51 Fig.1 of No.7 P.298 FIG. 11-37 Fig.2 P.412 FIG. 15-60 Fig.3 P.506 FIG. 18-58 Fig.4 P.442 FIG. 16-45 Fig.5 P.358 FIG. 13-54 -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 220.139.17.31
ptt789789:是180分鐘喔 01/18 10:26
tiesto1114:對吼搞錯了XD 01/18 17:21
※ 編輯: tiesto1114 來自: 220.139.8.178 (01/18 17:21)