课程名称︰ 普通物理学甲上
课程性质︰ 资工系大一必修 (物化生三选一)
课程教师︰ 王名儒
开课学院：
开课系所︰
考试日期（年月日）︰ 2015/01/16
考试时限（分钟）： 基本上是两节课 但写不完助教都会通融
试题 :
1. A solid cylinder with mass M & radius R is attached to a horizental spring
with force constant k. If it is perturbed a bit, it will roll without slipping
along the horizental surface. Find out the period of this simple harmonic
oscillation.
2. Three string waves propagating towards +x direction with functional forms
Asin(kx-ωt-π/3), Asin(kx-ωt) and Asin(kx-ωt+π/6). Find out the functional
form of the combined wave.
3. What is the rate of energy transmission of the following wave:
y(x,t)=Asin(kx-ωt) on a string with linear density μ? It is known that the
potnetial energy is the same as the kinetic energy of a simple harmonic wave
traveling on a string.
4. Two trains are traveling toward each other with a fixed speed ±30m/sec
relative to the ground. One train is blowing a whistle at 500Hz. What frequency
is heard on the other train?
5. Describe three different heat transfer mechanism. If there is theorical
formula to describe the heat transfer property of a material or related
mechanisms, you should write them down.
6. What is the maximum efficiency of a heat engine to operate between the warm
layer (30*C) of sea water and the cold deep layer (5*C)?
7. Write down the Maxwell distribution of the molecular speed of an ideal gas.
Determine the ratio of the probability for gas molecules at 250K to have a
speed of 250m/s to the probability of gas molecules at 150K to have the same
speed. The molar mass of the gas molecules is 39.9g/mol.
8. A small piece of metal with temprature Tx is put in contact with a heat
reservoir (temperature T). Prove that the above process is irreversible if Tx
is not equal to T.
9. What is the entropy change for an ideal gas undergoing free expansion to
four times of its original volume?
10. Find the electric field at a point (x,y,z) due to a charge q located at d/2
and a charge -q at -d/2 on the Z axis. Is the field strength still proportianal
to r^(-2)? (z>>d)