JEE Main20202 Sep 2020Morning ShiftPhysicsMagnetic Effects of CurrentActual
A charged particle (mass m and charge q ) moves along X axis with velocity V 0 . When it passes through the origin it enters a region having uniform electric field E → = - E j ^ which extends upto x = d . Equation of path of electron in the region x > d is:
Options
- Ay = qEd mv 0 2 x - d
- By = qEd mv 0 2 d 2 - x
- Cy = qEd mv 0 2
- Dy = qEd 2 mv 0 2 x
Correct answer
B. y = qEd mv 0 2 d 2 - x
Step-by-step solution
x > d   path is straight line - y - 1 2 a t 2 x - d = a t V 0 - y - 1 2 a t 2 a t = x - d V 0 - y a t - 1 2 d V 0 = x V 0 - d V 0 - m y V 0 q E d = x V 0 - d 2 V 0 y = - q E d m V 0 x V 0 - d 2 V 0 y = q E d m V 0 2 d 2 - x .