What is $\backslash$Delta vec$($B$)$ on the z$-$axis at z$=4\mathrm{.}00$m $?$

$\backslash$Delta vec$($B$)=$

T

in the

direction.

hat$($i$)$

hat$($j$)$

hat$($k$)$ Classify the situations according to whether or not they produce a magnetic field.

Prodinac a mornatic fiald

Does not produce a magnetic field

Answer Bank

A proton next to an electron, both at rest

An electron moving with a non$-$zero velocity

A long wire carrying a changing current

A long straight wire attached to the positive terminal of a battery