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Current Electricity — Physics STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 SciencePhysicsCurrent Electricity1 Mark
MCQ
Two non-ideal batteries are connected in parallel. Consider the following statements:
  1. The equivalent emf is smaller than either of the two emfs.
  2. The equivalent internal resistance is smaller than either of the two internal resistances.
  • A
    Both A and B are correct.
  • B
    A is correct but B is wrong.
  • C
    B is correct but A is wrong.
  • D
    Both A and B are wrong.
✓

Answer

  1. B is correct but A is wrong.

Explanation:

Equivalent emf $\in_0=\frac{\in_1\text{r}_1+\in_2\text{r}_2}{\text{r}_1+\text{r}_2}$

Equivalent resistance $=\text{r}_0=\frac{\text{r}_1\text{r}_2}{\text{r}_1+\text{r}_2}$

$\phi$ The equivalent emf is smaller than either of the two emfs.

$\phi$ The equivalent internal resistance is smaller than either of the two internal resistances.

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