A pair of adjacent coils has a mutual inductance of 2.5 H. If the current in one coil changes from 0 of 40 A in 8.0 s, then the change in flux linked with the other coil is.

Options

A. 100 Wb
B. 120 Wb
C. 200 Wb
D. 250 Wb

Explanation

To solve the problem, we will follow these steps:

### Step 1: Understand the given data
- Mutual inductance (M) = 2.5 H
- Initial current (I1) = 0 A
- Final current (I2) = 40 A
- Time (t) = 8.0 s

### Step 2: Calculate the change in current (di)
The change in current (di) can be calculated as:
\[ di = I2 - I1 \]
Substituting the values:
\[ di = 40\, A - 0\, A = 40\, A \]

### Step 3: Use the formula for change in flux (dΦ)
The change in magnetic flux (dΦ) linked with the other coil can be calculated using the formula:
\[ dΦ = M \cdot di \]
Where:
- M = mutual inductance
- di = change in current

### Step 4: Substitute the values into the formula
Substituting the values we have:
\[ dΦ = 2.5\, H \cdot 40\, A \]

### Step 5: Calculate dΦ
Now, calculating the above expression:
\[ dΦ = 100\, Weber \]

### Conclusion
The change in flux linked with the other coil is:
\[ dΦ = 100\, Weber \]

### Final Answer
The correct option is **100 Weber**.

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