Physics Times 07.2019

8. Thin hollow cylinder
   0 0
   2 ; ,^2

J i
B r r R J
R

 

    

 





 2 0 0;

i

B r R

r





 

r R B  0

2

i

r R B

r





 

9. Magnetic field due to a Solenoid
   Field at a point on the axis of a solenoid is

(^0) (sin sin )
2
ni
B

  
 For a long solenoid magnetic induction on the axis
is B ni 0 (  90 )^0
 At one end of a long solenoid magnetic induction
is^0
2
Bni
(^) (0 ,^0 90 )^0
 Magnetic field outside the solenoid is
approximately zero.
10.

B due to a Toroid

8. Thin hollow cylinder


9. Magnetic field due to a Solenoid
   







10. due to a Toroid


11. Force on a Charge Moving in
    

0

2

B Ni

r





 (r >> diameter of the core of the toroid)

11. Force on a Charge Moving in



B

 When a charged particle having charge q travels

with velocity v



in magnetic field B



it experiences

a force F given by F q v B ( )

  