Question

A uniform but time varying magnetic field exists in cylindrical region and directed into the paper. If field decrease with time and a positive charge placed at any point inside the region, then it moves-

• A. Along 1
• B. Along 2
• C. Along 3
• D. Along 4

Answer 1

Answer: (C)

Along 3

Answer 2

$\int_{}^{}{E.d\mathcal{l}}$= – pr² $\frac{dB}{dt}$

E×2pr = + pr² × $\frac{dB}{dt}$ as $\frac{dB}{dt}$= – ve

E = + ve

\ assume direction is right

so q charge move along 3