#### Question

A Boeing 747 with a $65-\mathrm{m}$ wingspan is cruising northward at $250 \mathrm{m} / \mathrm{s}$ toward Alaska. The $\vec{B}$ field at this location is $5.0 \times 10^{-5} \mathrm{T}$ and points $60^{\circ}$ below its direction of travel. Determine the potential difference between the tips of its wings.

#### Solution

Verified#### Step 1

1 of 2We know that the induced emf is equal to the negative rate change of magnetic flux and expression is given by:

$\varepsilon=\bigg |\dfrac{\Delta \phi}{\Delta t}\bigg | =BLv \cos \theta$

Now plug in the required value in the above equation and solve

$\begin{align*} \varepsilon&=(5 \cdot 10^{-5} \ \text{T})65 \ \text{m} (250 \ \frac{\text{m}}{\text{s}}) \cdot \cos 30\text{\textdegree}\\ &=0.704 \ \text{V} \end{align*}$

$\boxed{\color{#c34632}\varepsilon=0.704 \ \text{V}}$