Question

A conducting rod $PQ$ of length $L=1.0m$ is moving with a uniform speed $v=20m/s$ in a uniform magnetic field $B=4.0T$ directed into the paper A capacitor of capacity $C=10\mu F$ is connected as shown in figure. Then

• A. $q_A=+800\mu C$ and $q_B=-800\mu C$
• B. $q_A=-800\mu C$ and $q_B=+800\mu C$
• C. $q_A=0=q_B$
• D. charged stored in the capacitor increases exponentially with time

Answer 1

The correct option is A $q_A=+800\mu C$ and $q_B=-800\mu C$

According to Fleming’s right-hand rule induced current flows from Q to P.

Hence P is at higher potential and Q is at lower potential.

Therefore A is positively charged and B is negatively charged.

Hence:

$q_A=+800\mu Cand{q}_b=-800\mu C$