The power loss π in a resistor is calculated using the formula: π =π2/R The uncertainty in the potential difference π is 3% and the uncertainty in the resistance π is 2%. What is the uncertainty in π?
Correct answer: C. 8%
- A. 4%
- B. 7%
- C. 8%
- D. 11%
Explanation
β’The fractional error in V would be3Γ2=6β’The fractional error in R would be2β’So the fractional error of power would be equal to the sum of the fractional errors of both potential difference and resistance;6+3=8β’NOTE= The given % error is multiplied by the power as in case of potential difference.
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