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MODEL PAPER 10 — Physics STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 SciencePhysicsMODEL PAPER 101 Mark
MCQ
Assertion (A): Positive charge always moves from a higher potential point to a lower potential point. 
Reason (R): Electric potential is a vector quantity.
  • A
    Both A and R are true and R is the correct explanation of A
  • B
    Both A and R are true but R is not the correct explanation of A.
  • C
    A is true but R is false.
  • D
    A is false but R is true.
✓

Answer

(c) A is true but R is false.
Explanation: If two points P and Q in an electric field are separated by an infinitesimal distance $\Delta x$ and have a potential difference $\Delta V$
between them, $E =\frac{-\Delta V}{\Delta x}$. Here, negative sign implies that $\vec{E}$ has got a direction opposite to the potential gradient, i , e, in the
direction of $\vec{E}$, the potential decreases, i. e, positive charge always moves from a higher potential point to a lower potential point.

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