A long straight conductor carrying a current of 4 A is in parallel to another conductor of length 5 cm and carrying a current 9 A. They are separated by a distance of 10 cm. Calculate (a) B due to first conductor at second conductor (b) The force on the short conductor.

Explanation

To solve the problem, we will break it down into two parts as requested:

### Part (a): Calculate the Magnetic Field (B) due to the first conductor at the location of the second conductor.

1. **Identify the given values**:
- Current in the first conductor, \( I_1 = 4 \, \text{A} \)
- Current in the second conductor, \( I_2 = 9 \, \text{A} \)
- Length of the second conductor, \( l = 5 \, \text{cm} = 0.05 \, \text{m} \)
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