JEE Main 2019 — Electrostatics Question with Solution
From: JEE Main 2019 (Online) 12th January Morning Slot
Question
There is a uniform spherically symmetric surface charge density at a distance R0 from the origin. The charge distribution is initially at rest and starts expanding because of mutual repulsion. The figure that represents best the speed V (R(t)) of the distribution as a function of its instantaneous radius R (t) is :
Choose an option
Show full solutionCorrect option: B
Correct answer
B
Step-by-step explanation
At any instant 't'
Total energy of charge distribution is constant
i.e.
V =
V = = C
Also the slope of v-s curve will go on decreasing
Total energy of charge distribution is constant
i.e.
V =
V = = C
Also the slope of v-s curve will go on decreasing
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