1. @prof_Ahmad07
v
c
v≤c
v<<<c
10 -15
Fm
d
10 -10
A0
1
10-2
10-13
10-40
1

2. @prof_Ahmad07
-
–
–
2

3. @prof_Ahmad07
–-
s
s/
y
y/
u
x/
ut
x
o
z
o
.A
x/
/
z/
t
(x,y,z)
(x,y,z,t)
X+
o=o/
t
S/
u
t=t/
o&o/
(x/,y/,z/,t/) (x,y,z,t)
A
x / = ut – x --------------------- 1
y / = y -------------------------- 2
z / = z -------------------------- 3
t / = t --------------------------- 4
–
x = ut + x /
y=y/
z=z/
t=t/
3
1,2,3,4

4. @prof_Ahmad07
–
dt = dt /
t=t/
dx / dt / = vx / , dy / dt / = vy / , dz / dt / = vz /
dx / dt = vx , dy / dt = vy
, dz / dt = vz
then :
vx / = vx – u ---------------- 5
vy / = vy -------------------- 6
vz / = vz -------------------- 7
–
7
4
1

5. @prof_Ahmad07
s/
( m1 , m2 )
s
m1v1+m2v2 = m1v1+m2v2
m1(v1-u) + m2(v2-u) = m1(v1-u) + m2(v2-u)
m1v1 – m1u + m2v2 – m2u = m1v1 – m1u + m2v2 – m2u
m1v1 + m2v2 – u(m1+m2) = m1v1 + m2v2 – u(m1+m2)
Then : m1v1+m2v2 = m1v1+m2v2
5

6. @prof_Ahmad07
1/2m1v21 + 1/2m2v22 = 1/2m1v21 + 1/2m2v22
1/2m1(v1 – u )2 + 1/2m2(v1 – u )2 = 1/2m1(v1 – u )2 + 1/2m2(v1 – u )2
1/2m1(v12 – 2v1u + u2 ) + 1/2m1(v22 – 2v2u + u2 ) = 1/2m1(v12 – 2v1u + u2 ) + 1/2m1(v22 – 2v2u + u2 )
1/2m1v12 – m1v1u + 1/2m1u2 + 1/2m2v22 – m2v2u + 1/2m2u2 = 1/2m1v12 – m1v1u + 1/2m1u2 + 1/2m2v22 – m2v2u
+ 1/2m2u2
1/2m1v12 + 1/2m2v22 + 1/2m1u2 + 1/2m2u2 – u(m1v1 + m2v2 ) = 1/2m1v12 + 1/2m2v22 + 1/2m1u2 + 1/2m2u2 –
u(m1v1 + m2v2 )
1/2m1v21 + 1/2m2v22 = 1/2m1v21 + 1/2m2v22
6

7. @prof_Ahmad07
S/ S
-
S
q
S
q
/
E
c
7
F = qE
v