GATE 2015 EE – SET 2 – Question 12

For$$ V_{c}$$ = 2
$$R_{c} $$= $${\frac{10-V_{c}}{I_{c}}}$$ = $$\frac{10-2}{I_{c}}$$ =$$ \frac{8}{I_{c}}$$

For $$V_{c}$$ = 4 ,

$$\acute{R_{c}}$$ = $${\frac {10-V_{c}}{I_{c}}}$$ = $$\frac{10-4}{I_{c}}$$ = $$\frac{6}{I_{c}}$$

$$\frac{\acute{R_{c}}}{R_{c}} $$= $$\frac{\frac{6}{I_{c}}}{\frac{8}{I_{c}}}$$=$$\frac{6}{8}$$= 0.75