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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): Range of Coulomb force is infinite.
Reason (R): Coulomb force acts between two charged particles.
✓

Answer

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

Explanation:

Coulomb's force or electric force given by Coulomb's law is valid over nuclear distances $(\cong10^{-15}\text{m})$ as well as over very large distances.

From Coulomb's law, $\text{F}=\frac{\text{k }\mid\text{ q}_1 \parallel\text{ q}_2 \mid}{\text{r}^2}.$ This generally holds only for charged objects whose size are much smaller than the distance between them.

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