magnetism ncert q
how to do the 2nd part, i got the diagram and stuff but im not able to conclude to the answer
24 Replies
@Gyro Gearloose
Note for OP
+solved @user to close the thread when your doubt is solved. Mention the user who helped you solve the doubt. This will be added to their stats.@(Bee)guyman any inputs?
heylo anyone?
लोल sorry. @Gyro Gearloose any inputs?
one sec
Assume the distance is k
The diagram looks somewhat like this
We now have x= R/2 + k
Since the current in the coils is in the same direction they produce a net magnetic field in the same direction, hence we add
From this expression for B, ignore the 2 and the numerator because they are constant
In fact, let's say
Comrade Rock Astley
We now add the magnetic field expressions
Comrade Rock Astley
We have
Comrade Rock Astley
We take R^3 out of the expression
Comrade Rock Astley
Since k is much less than R (and the exponent is greater than 1) we ignore the third term
Comrade Rock Astley
Use the binomial theorem to expand this
Comrade Rock Astley
We see that the first term (apart from 5/4) gets cancelled and the other terms are too small for our consideration
Hence we get
(my bad, the exponent is -3/2)
And we take R^-3 out
We get
Comrade Rock Astley
here you go
okay thank you so much
+solved @Comrade Rock Astley
Post locked and archived successfully!
Archived by
<@852788017243357194> (852788017243357194)
Time
<t:1716401903:R>
Solved by
<@769492044837552139> (769492044837552139)