Question

7 Ideal Solenoid - prediction To find out whether the Slinky is a good realization of an ideal solenoid, we will explore the magnetic field in the Slinky qualitatively. For each of the following regions, predict the results of the net magnetic field compared to the value B1 (near the center of the loop, in the middle of the Slinky). Decide whether the value should be the same, larger, smaller or zero. B. B6 COOOO000 B. B2 B3 BA Hypothesis for ideal solenoid (see also the figure above): 1. Net magnetic field B1 (near the center of the loop, in the middle of the Slinky): B1= B1 2. Net magnetic field B2 (near the edge of the loop, in the middle of the Slinky): 3. Net magnetic field B3 (near the center of the loop, at the end of the Slinky):

Answer 1

As we know that the magnetic field for solenoid is given as,

B = UonI = UoNI/L

And at its center it will be maximum and till to the surface it is approximately constant but decreases outside of it if the length of solenoid is very large.

Now in case if slinky When we take a metal Slinky then it will serve similarly as solenoid and When a current passes through the wire of slinky then, a magnetic field is present inside the slinky which would give similarly value as compared to the solenoid so that,

1. Same ,

Because both will serve as same configurations.

2. Smaller, at B2 as compared to B1

Because as we move towards the end of the coil we will get the reduced value of magnetic field of we can say that nearly half the value of magnetic field as that present at B1

3.same

As both B1 and B3 are lie along the same line of axis.