課程名稱︰普通物理學甲下
課程性質︰數學系大一必修
課程教師︰張寶棣
開課學院：理學院
開課系所︰數學系
考試日期（年月日）︰2015/6/25
考試時限（分鐘）：10:20~12:10
試題 :
1. Please answer the following questions.
‧What is right-handed elliptically polarized light? What is Fermat's
principle in explaining the reflection and refraction of light? (5%)
‧Explain the cause of magnetism. Why does diamagnetism dominate over
paramagnetism in most materials at sufficiently high temperature? (5%)
‧Use Huygen's principle to explain reflection and refraction. (5%)
2. In the circuit shown in Fig.1, assume that all parameters are given. (a)
Find the current as a function of time. (b) Find the power delivered to the
circuit. (c) Find the current as a function of time after switch 1 is
opened. (d) After the switch 2 is also opened, find the phase of the current
and voltage. (e) Find the impedance of the circuit when both switches are
open. (f)Find the maximum energy stored in the capacitor during oscillation.
(g) Find the maximum energy stored in the inductor during oscillation. (h)
Now the frequency of the voltage source is doubled. Find the phase
difference between the current and the voltage. (i) Find the frequency that
makes the inductive reactance half the capacitive reactance. (24%)
S
1
———○———○———
▕ ▕
▕ ▕
▕ ▕
———————﹏﹏﹏———————
▕ L ▕
▕ ▕
▕ ▕————————
＼ ▕ ▕
／ ▕ ○
／ ——— ▕ S
R ＼ ——— C ▕ 2
＼ ▕ ○
／ ▕ ▕
／ ▕ ▕
＼ ▕————————
▕ ▕
▕ __ ▕
▕ ／ ＼ ▕
——————/ ~~ \———————
＼__／
Δv(t) = ΔV cos ωt
max
3. The transformer show in Fig.2 has two secondary windings: one supplies 220V,
the other, 11 V. The input voltage at the primary coil is 110 V. If the 220V
secondary has N turns, how many turns does the 11-V secondary coil have?(6%)
4. The magnitude of the electric field between the two circular parallel plates
5 4
in Fig.3 is E = (4.0 ×10 ) - (6.0 ×10 t), with E in volts per meter and t
→ -2 2
in seconds. At t = 0, E is upward. The plate area is 6.0 ×10 m . For t≧0,
what are the (a) magnitude and (b) direction(up or down) of the displacement
current between the plates (c) Is the direction os the induced magnetic
field clockwise or counterclockwise in the figure? (10%)
2
5. A plane electromagnetic wave has an intensity of 750 W/m . A flat,
rectangular surface of dimensions of 50 cm ×100 cm is placed perpendicular
to the direction of the wave. The surface absorbs half of the energy and
reflects half. Calculate (a) the total energy absorbed by the surface in
1.00 s and (b) the momentum absorbed in this time. (10%)
6. We want to rotate the direction of polarization of a beam of polarized light
。
through 90 by sending the beam through one or more polarizing sheets. (a)
What is the minimum number of sheets required? (5%) (b) What is the minimum
number of sheets required if the transmitted intensity is to be more than
60% of the original intensity? (5%)
7. The reflected light from an oil film floating on water shows destructive
interference for light of wavelength 550 nm, 610 nm, and 685 nm incident
along the normal. The index of refraction of the oil is n = 1.40. What is
the oil minimum possible thickness? (10%)
8. Light that has a wavelength equal to 550 nm illuminates two slits that both
have widths equal to 0.030 mm and separations equal to 0.15 mm. (a) How many
interference maximum fall within the full width of the central diffraction
maximum? (b) What is the ratio of the intensity of the third interference
maximum to the side of the centerline to the intensity of the center
interference maximum? (10%)
9. A spy satellite is announced to be capable of distinguishing detail of 10
inches across. If the satellite orbits at a height of 220 mi, what must be
the minimum size of the lens aperture, assuming maximum sensitivity at
λ = 525 nm? (5%)