Answer
a) $v=5.75m/s$
b) remains the same
Work Step by Step
We can find the required speed as follows:
$\mathcal{E}=IR=(0.155)(12.5)$
$\mathcal{E}=1.94V$
Now $v=\frac{\mathcal{E}}{Bl}$
We plug in the known values to obtain:
$v=\frac{1.94}{(0.750)(0.450)}$
$v=5.75m/s$
(b) Since $v=\frac{\mathcal{E}}{Bl}$, this equation shows us that the speed does not depend on the direction of motion. Hence, the answer to part(a) would not change.
