Answer:
The value is 
Explanation:
From the question we are told that
The diameter of the ring is 
The length of the solenoid is 
The diameter of the solenoid is 
The number of turns is N = 1500
The change in current in the solenoid is 
The time taken is 
Generally the radius of the ring is

=> 
=> 
Generally the area of the ring is mathematically represented as

=>
=> 
Generally the induced emf is mathematically represented as

Here

Here
is the permeability of free space with value

So

=> 
So

=> 
Series,effective resistance =R₁+R₂+R₃...
parallel,effective resistance 1/R=1/R₁ +1/R₂ +1/R₃...
Here,effective resistance 1/R =1/7 +1/5+ 1/4+1/2
=1.092
R = 1/1.092 =0.915Ω
voltage V=9 V
current I=V/R
I=9 / 0.915
=9.83 A
Answer:
the force of the friction is A-0.52