# What is the value of B at the instant E reaches its maximum value?

1. Dec 6, 2007

### samee

1. The problem statement, all variables and given/known data
The magnetic field inside a 4.0-cm-diameter superconducting solenoid varies sinusoidally between 8.0 T and 12.0 T at a frequency of 10 Hz.
Pt. 1--> What is the maximum electric field strength at a point 1.5 cm from the solenoid
axis?
Ans.- -> 0.942 V/m
Pt. 2--> What is the value of B at the instant E reaches its maximum value?

2. Relevant equations

E=cB

3. The attempt at a solution

.942/c=3.14*10^-9

Which is the wrong answer. I can't find any other relationships between E and B! Help please!

2. Dec 14, 2007

### vector3

The link below has a number of relationships like

$$\nabla \times E =- \frac{\partial B}{\partial t}$$

http://en.wikipedia.org/wiki/Maxwell%27s_equations" [Broken]

Last edited by a moderator: May 3, 2017