Question

A conductor rod AB moves parallel to X- axis in a uniform magnetic field, pointing in the positive Z-direction. The end A of the rod gets-

• A. positively charged
• B. negatively charge
• C. neutral
• D. first positively charged and then negatively chrged

Answer 1

The correct option is B negatively charge

We know that the force on a charge is given by $F=q\overrightarrow{v}\times \overrightarrow{B}$

Here, on a positive charge, $\hat{v}=\hat{i}$ and $\hat{B}=\hat{k}$

Hence, force on a positive charge is along $\hat{i}\times \hat{k}=-\hat{j}$

Hence, end B got positively charged and end A get negatively charged.

Answer-(B).