課程名稱︰普通物理學甲上
課程性質︰數學系大一必帶
課程教師︰黃暉理
開課學院：理學院
開課系所︰數學系
考試日期（年月日）︰2013/12/17
考試時限（分鐘）：60
是否需發放獎勵金：是
（如未明確表示，則不予發放）
試題 :
1. A sound source S is stationary, and a detector D is moving toward it from A
at speed v. Then turn right by 90 degree at point B. If the sound intensity
is I , detected frequency is f at A. (40 pt)
0 0
(a) What is the intensity I , I at B and C?
B C
(b) What is the frequency f emitted by S?
S
(c) What is the detected frequency f at C?
C
●
C│
│R
│ 1
●───●──●
S R B R A
1 2
2. A gas sample expands from V to 4V while its pressure decreases from P to
0 0 0
P /4. How much work is done by the gas if its pressure changes with volume
0
via (a) path A, (b) path B, and (c) path C? (30 pt.)
A
P ┌─→─┐
0 │╲ │
↓ ↘B ↓
│C ╲│
P /4 └─→─┘
0
V 4V
0 0
γ
3. For ideal gas in an adiabatic process, we have PV = const. (a) Prove it.
a
And TV = const. (b) Find a? (30 pt.)