When the forwward bias voltage of a diode is changed from `0.6` V to `0.7` V the current changes from 5 mA to 15 mA. Then its forward bias resistance is

Answer

To find the forward bias resistance of the diode, we can use the formula for resistance in terms of voltage and current changes:

\[ R = \frac{\Delta V}{\Delta I} \]

### Step 1: Identify the changes in voltage and current.
- The initial voltage (\(V_i\)) is 0.6 V.
- The final voltage (\(V_f\)) is 0.7 V.
- The initial current (\(I_i\)) is 5 mA.
- The final current (\(I_f\)) is 15 mA.

### Step 2: Calculate the change in voltage (\(\Delta V\)).
\[ \Delta V = V_f - V_i = 0.7 \, \text{V} - 0.6 \, \text{V} = 0.1 \, \text{V} \]

### Step 3: Calculate the change in current (\(\Delta I\)).
\[ \Delta I = I_f - I_i = 15 \, \text{mA} - 5 \, \text{mA} = 10 \, \text{mA} \]
Since we need to convert milliampere to amperes:
\[ \Delta I = 10 \, \text{mA} = 10 \times 10^{-3} \, \text{A} = 0.01 \, \text{A} \]

### Step 4: Substitute the values into the resistance formula.
\[ R = \frac{\Delta V}{\Delta I} = \frac{0.1 \, \text{V}}{0.01 \, \text{A}} = 10 \, \Omega \]

### Step 5: Final calculation.
The forward bias resistance of the diode is:
\[ R = 10 \, \Omega \]

### Summary of the solution:
The forward bias resistance of the diode is \(10 \, \Omega\).

---