Understanding Magnetic Fields Flashcards - High School Physics

Ampere's law states:

$B=\frac{\mu_0 I}{2\pi r}$ .

In other words, the magnetic field (), is equal to a constant ( $\mu_0$ ) times the current () divided by the circumference of the magnetic field it is creating.

We are given the current, the constant, and the magnetic field strength. Using these values, we can solve for the magnetic field radius.

$B=\frac{\mu_0 I}{2\pi r}$

$150T=\frac{(4\pi*10^{-7}\frac{T\cdot m}{A})(6.6*10^8A)}{2\pi r}$

Notice that the $\pi$ cancels out.

$150T=\frac{(4*10^{-7}\frac{T\cdot m}{A}) (6.6*10^8A)}{2r}$

$150T=\frac{264T\cdot m}{2r}$

$150T=\frac{132T\cdot m}{r}$

$r=\frac{132T\cdot m}{150T}$

Understanding Magnetic Fields - High School Physics

A current of runs through a straight wire. If the resulting magnetic field is , what is the radius of the field?

$\small \mu_0=4\pi*10^{-7}\frac{T\cdot m}{A}$