An electric wire is connected across a cell of e.m.f. E. The current I is measured by an ammeter of resistance R. According to ohm's law:
Correct answer: B. E=IR
- A. E=I2R
- B. E=IR
- C. E=R/I
- D. E=I/R
Explanation
Ohm's Law describes the relationship between voltage, current, and resistance for a component. For the entire circuit, the total EMF (E) equals the total current (I) multiplied by the total resistance (Rtotal). This is a direct application of the law.
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