To solve the problem, we need to find the length of the conductor moving in a magnetic field, which induces an emf. We are given:
- Speed \( v = 5 \, \text{m/s} \)
- Magnetic field \( B = 2 \, \text{T} \)
- Induced emf \( \varepsilon = 10 \, \text{V} \)
1. Understanding the Formula:
The emf induced in a straight conductor moving perpendicular to a magnetic field is given by:
\( \varepsilon = B \cdot l \cdot v \)
where:
- \( \varepsilon \) is the induced emf
- \( B \) is the magnetic field
- \( l \) is the length of the conductor
- \( v \) is the velocity
2. Substituting the Given Values:
\( 10 = 2 \cdot l \cdot 5 \)
3. Solving for \( l \):
\( 10 = 10l \)
\( l = \frac{10}{10} = 1 \, \text{m} \)
Final Answer:
The length of the conductor is \({1 \, \text{m}} \).
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An infinite wire has a circular bend of radius \( a \), and carrying a current \( I \) as shown in the figure. The magnitude of the magnetic field at the origin \( O \) of the arc is given by: