To find the induced electromotive force (emf) in a straight wire moving through a magnetic field, we can use the formula:
\[ \text{emf} = B \cdot L \cdot v \]
where:
- \( B \) is the magnetic field strength (in teslas),
- \( L \) is the length of the wire (in meters),
- \( v \) is the velocity of the wire (in meters per second).
Given:
- \( B = 1.0 , \text{T} \),
- \( L = 30.0 , \text{m} \),
- \( v = 2.0 , \text{m/s} \).
Now, plugging in the values:
\[ \text{emf} = 1.0 , \text{T} \cdot 30.0 , \text{m} \cdot 2.0 , \text{m/s} \]
Calculating this:
\[ \text{emf} = 1.0 \cdot 30.0 \cdot 2.0 = 60.0 , \text{V} \]
So, the induced emf is \( 60 , \text{V} \).
Therefore, the correct answer is 60 V.