Question

Q. 31Derive the quantity for bohr magneton and also
state its value.
Rowland ring of mean radius 15 cm has 3500
turns of wire wound on a ferromagnetic core of
relative permeability 800. What is the magnetic
field B in the core for a magnetizing current 1.2 A?​

Answer 1

see attachment for the answer...

Answer 2

Text Solution

Solution :

Mean radius of a Rowland ring,

r = 15cm = 0.15cm

<br> Number of turns on a ferromagnetic core,

N = 3500

<br> Relative permeability of the core material,

μr = 800

<br> Magnetising current,

I=1.2A

. <br> The magneic field is given by the relation: <br>

B = μ1μ01N/2πr

<br> where, <br>

μ0 =

permeabilityof free space=

4n × 10power-7 TmA-1 power

<br>

B = 800 × 4π × 10power-7 × 1.2×3500 / 2π × 0.15 =

<br> Therefore, the magnetic field in the core is 4.48T.