Answer:


-0.020475 V
Explanation:
= Vacuum permeability = 
= Number of turns of coil = 25
= Number of turns of coil 2 = 300
= Rate of current increased = 
d = Diameter = 2 cm
r = Radius = 
A = Area = 
Magnetic field in the solenoid is given by

Magnetic flux is given by

The average magnetic flux through each turn of the inner solenoid is
Mutual inductance is given by

The mutual inductance of the two solenoids is 
Induced emf is given by

The emf induced in the outer solenoid by the changing current in the inner solenoid is -0.020475 V
Answer:
thanks so much lol can I get brainliest
Explanation:
Answer: we need B/√2 for having twice the energy i.e 0.17B
Explanation:
This is actually a simple one, so i will guide you through it.
We know that Energy here means Kinetic Energy (K.E)
and the expression is given thus;
Energy = 1/2 mv2
and velocity v = E/B
let us make x the energy intially, foe electric field E, magnetic field B, mass m
so, x = 1/2 m (E/B)2
we have to find magnetic field for which twice the energy so , let magnetic field be y, so
2x = 1/2m(E/y)2
y = B/√2 = 0.17B
therefore, we need B/√2 for having twice the energy
cheers i hope this helps!!!!