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Electric Charges and Fields — Physics STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 SciencePhysicsElectric Charges and Fields1 Mark
Question
For two statements are given-one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given below.
  1. Both A and R are true, and R is the correct explanation of A.
  2. Both A and R are true, but R is not the correct explanation of A.
  3. A is true but R is false.
  4. A is false and R is also false.
Assertion (A): As force is a vector quantity, hence electric field intensity is also a vector quantity.
Reason (R): 'Tile unit of electric field intensity is newton per coulomb.
✓

Answer

  1. Both A and R are true, but R is not the correct explanation of A.

Explanation:

The electric field intensity is equal to force experienced by unit positive test charge q0 placed at that point i.e.

$\vec{\text{E}}=\frac{\vec{\text{F}}}{\text{q}_0}$ thus $\vec{\text{E}}$ is also a vector quality,

As, $\text{E}=\frac{\text{F}}{\text{q}}=\frac{\text{newton}}{\text{coulomb}}.$

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