1 =A+ B c λ2 · A B 810 f 1 A 1 t x 1 X 1 =A 1 sinw 1 t =A 1 sin2 𝜋𝑓1 x 2 f 2 A 2 X 2 =A 2...
7
. λ 1 c =A+ B λ 2
Transcript of 1 =A+ B c λ2 · A B 810 f 1 A 1 t x 1 X 1 =A 1 sinw 1 t =A 1 sin2 𝜋𝑓1 x 2 f 2 A 2 X 2 =A 2...
.
λ
1
c= A +
B
λ2
.
A
810B
t1A1f
1x
𝜋𝑓1𝑡sin21t =A1sinw1=A1X
2A2f2x
𝜋𝑓2𝑡sin22t =A2sinw2=A2X
xt
2+x1X= x
t2sinw2t + A1sinw1A
2+A1A=A
t2t+A sinw1X = A sinw
𝑥 = 2𝐴 𝑐𝑜𝑠 (𝑤2−𝑤1
2) 𝑡 𝑠𝑖𝑛 (
𝑤2−𝑤1
2) 𝑡
1,w2w10Hz (
.
𝑓2 − 𝑓1 = ∆𝑓 ≤ 10𝐻𝑧
∴ 𝑥 = 𝐵 𝑠𝑖𝑛 (𝑤2−𝑤1
2) 𝑡
𝐵 = 2𝐴 𝑐𝑜𝑠 (𝑤2−𝑤1
2) 𝑡
B
𝑠𝑖𝑛 (𝑤2+𝑤1
2)
12𝐴≤ 𝐵 ≤
2A𝑐𝑜𝑠 (𝑤2−𝑤1
2) 𝑡 = ±1
N0,1,2,…
T τ =
1
𝑓2−𝑓1=
1
∆f
f∆
B𝑐𝑜𝑠 (𝑤2−𝑤1
2) 𝑡 = 0
(100cm(101cm
𝑓 = 𝑣
λ=
𝑣
100
𝑓 = 𝑣
λ=
𝑣
101
.
3 =
18
6
𝑓2 − 𝑓1 = 𝑣
100−
𝑣
101= 3
V=303m/sec
1-
ζ = asin(𝑤𝑡 − 𝑘𝑥) , 𝑤 = 𝑘𝐶 , 𝑘 =2𝜋
𝜆
𝜁 = 𝑎𝑠𝑖𝑛2𝜋
𝜆(𝑐𝑡 − 𝑥)
C
𝑢 =𝑑𝜁
𝑑𝑡=
2𝜋𝑎𝑐
𝜆 𝑐𝑜𝑠
2𝜋
𝜆 (𝑐𝑡 − 𝑥)
uc
u
.
2-
. 𝑉𝑝ℎ = 𝑤
𝑘 = 𝜆𝑓
x-ut
x2f(x) = x 2ut)-ut) = (x-f (x
xtx,t
4
p
x-ut=constant
𝑑𝑥
dt− u = 0 ⇒
dx
dt= u
dx
dtphase velocity
سرعة المجموعة -3
Vg = ∂w/∂k
.
𝑉p =w
k ⇒ w = 𝑣𝑝𝑘
dw = 𝑣𝑝. 𝑑𝑘 + 𝑘. 𝑑𝑣𝑝
𝑣𝑔 =𝑑𝑤
𝑑𝑘=
𝑣𝑝.𝑑𝑘+𝑘.𝑑𝑣𝑝
𝑑𝑘= 𝑣𝑝 + 𝑘
𝑑𝑣𝑝
𝑑𝑘
جسيي -ازدواجية موجة
التداخلأطوارموجات جيبية
هدامتداخلا
الدالة الموجيةبكمية حركة
c
1-sec
.
1-cm
tx
k
