Question

magnetic field = 0.192 t *
wire length = 0.78 m
relative speed =
emf = 3.00 v
20 m/s
60 m/s
5.28 m/s
0.920 m/s

Explanation:

Step1: Recall the formula for motional EMF

The formula for motional EMF is $\mathcal{E}=BLv$, where $\mathcal{E}$ is the electromotive force, $B$ is the magnetic field, $L$ is the length of the wire, and $v$ is the relative speed.

Step2: Solve for $v$

Rearrange the formula to solve for $v$: $v = \frac{\mathcal{E}}{BL}$.
Substitute the given values: $B = 0.192\ T$, $L = 0.78\ m$, and $\mathcal{E}=3.00\ V$.
$v=\frac{3.00}{0.192\times0.78}$.
First, calculate $0.192\times0.78 = 0.14976$.
Then, $v=\frac{3.00}{0.14976}\approx20\ m/s$.

Answer:

20 m/s