A current flows through a rectangular conductor in the presence of uniform magnetic field B pointing out of the page as shown. Then the potential difference `V_(P)-V_(Q)` is equal to (assume charge carriers in the conductor to be positively charged moving with a drift velocity of v )

Options

A. `Bvb`
B. `-Bvb`
C. `Bvc`
D. `-Bvc`

Answer

C

Explanation

`|epsilon|=B lv` where l is the edge perpendicular to both B and `vecv` i.e.c.
`therefore |epsilon|=B v c`.
Now by right hand thumb rule magnetic force an a positive charge moving towards right is in down wrd direction Hence end P will be positive.
`therefore V_(P)-V_(!)` is positive
`rArr epsilon=+Bvl`.