Step 1: In the CE configuration, the output is 180\(^\circ\) out of phase with the input, which is a characteristic feature of the common emitter configuration.
Step 2: In both CB and CC configurations, the phase shift is either zero or a fraction of a degree, not 180\(^\circ\). Hence, the only correct answer is the CE configuration. Thus, the correct answer is option (2), CE - configuration.
Sliding contact of a potentiometer is in the middle of the potentiometer wire having resistance \( R_p = 1 \, \Omega \) as shown in the figure. An external resistance of \( R_e = 2 \, \Omega \) is connected via the sliding contact.
The current \( i \) is :