QUESTION $4$

You plot the magnetic field $B(y-$axis$)$ vs the vertical position $d(x-$axis$),$ for the long, straight, horizontally$-$oriented current$-$carrying wire, and linearize as appropriate $($for some graphs, you need to linearize, for other you do not$).$ The other two controllable variables$-$current I and horizontal position $h-$are held constant. What does the slope of the line represent, physically?

slope $=2{}_0\frac{\text{I}}{h}$

slope $=2{}_{0}I$

slope $=2{}_{0}h$

line is horizontal, so slope $=0$

none of the above

QUESTI$$N $5$

You plot the magnetic field $B(y-$axis$)$ vs the horizontal position $h(x-$axis$),$ for the long, straight, horizontally$-$oriented currentcarrying wire, and linearize as appropriate $($for some graphs, you need to linearize, for other you do not$).$ The other two controllable variables$-$current I and vertical position d$-$are held constant. What does the slope of the line represent, physically?

slope $=2{}_0\frac{\text{I}}{d}$

slope $=2{}_{0}I$

slope $=2{}_{0}d$

line is horizontal, so slope $=0$

none of the above