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MODEL PAPER 9 — Physics STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 SciencePhysicsMODEL PAPER 91 Mark
MCQ
Assertion: Positive charge always moves from a higher potential point to a lower potential point.
Reason: Electric potential is a vector quantity.
  • A
    Assertion and reason both are correct statements and reason is correct explanation for assertion.
  • B
    Assertion and reason both are correct statements but reason is not correct explanation for assertion.
  • C
    Assertion is correct statement but reason is wrong statement.
  • D
    Assertion is wrong statement but reason is correct statement.
✓

Answer

(c) Assertion is correct statement but reason is wrong statement.
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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