32
- Force on a charge moving in
- Motion of a charged particle in magnetic
field
(I) When vis perpendicular to B
:
Radius
mv
qB
(since, qvB =
mv^2
r
)
Frequency 'n' =
qB
2 πm
Time period 'T' =
2 m
qB
(II) When the angle between v and B
is
(other than 0^0 , 90^0 (or) 180^0 )
m sin θ
qB
v
r
Time period=^2 πr =2πm
vsinθ qB
x=T v cos =θ 2 m v cosπ θ
qB
B & E
F q E v B ,
which is the famous
'Lorentz-force equation'.
- Cyclotron
The cyclotron is a device used to accelerate
charged particles or ions to high energy.
The period of revolution of charges is given by
1 2
c
T m
f Bq
Here fc is called the cyclotron frequency.
v BqR
m
- Magnetic Force on a current wire
F d F i dl B ( )
.
If magnetic field is uniform, i.e., B
= constant,
F i dl B i l B [ ] ( )
(1) Force between two long current wires
Force experienced per unit length of each
conductor is,
F
l
= 0 1 2
2
i i
r
where i 1 , i 2 , are the currents flowing through the
two conductors.
r is the perpendicular distance between them.
- Torque on a Current Carrying Coil
If the area vector of a coil makes an angle '' with
the direction of the uniform field of induction B
then
= nIABsin
M B
Where 'A' is area of the coil of 'n' turns carrying a
current I and magnetic moment of coil M nIA.
- P. E of a coil in uniform magnetic field
If the angle made by M of the coil with
- Motion of a charged particle in magnetic
field
- Force on a charge moving in &
- Cyclotron
- Magnetic Force on a current wire
- Torque on a Current Carrying Coil
- P. E of a coil in uniform magnetic field
B in
uniform magnetic field is ‘’, then its potential
energy U M B. U MB cos
.
.
.
