In a region of space, suppose there exists a uniform electric field $\vec{E}=10 i\left(\frac{ v }{ m }\right)$. If a positive charge moves with a velocity $\vec{v}=-2 \hat{j}$, its potential energy
A
Increases
B
Decreases
C
Does not change
D
Initially increases then decreases
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C
Does not change
c (c)
As charge moves perpendicular to $\vec{E}$, no change in energy occurs.
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