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Percentage Error Calculator

Percentage Error Formula:

\[ \text{Percentage Error} = \left| \frac{\text{Experimental} - \text{Theoretical}}{\text{Theoretical}} \right| \times 100\% \]

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1. What is Percentage Error?

Definition: Percentage error measures the accuracy of an experimental value compared to a theoretical or accepted value.

Purpose: It quantifies the difference between measured and true values as a percentage of the true value.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ \text{Percentage Error} = \left| \frac{\text{Experimental} - \text{Theoretical}}{\text{Theoretical}} \right| \times 100\% \]

Where:

Key Points:

3. Importance of Percentage Error

Applications: Used in scientific experiments, quality control, engineering, and any field requiring measurement accuracy assessment.

4. Using the Calculator

Instructions: Enter both experimental and theoretical values. The theoretical value must be non-zero.

5. Frequently Asked Questions (FAQ)

Q1: What's considered a good percentage error?
A: This depends on the field. In many scientific experiments, <5% is good, while engineering might require <1%.

Q2: Can percentage error be negative?
A: No, the absolute value makes it always positive. The sign of (Experimental - Theoretical) indicates direction of error.

Q3: What if my theoretical value is zero?
A: Percentage error is undefined when theoretical value is zero. Use absolute error instead.

Q4: How is this different from percent difference?
A: Percent error compares to a known value, while percent difference compares two experimental values.

Q5: Should I use more decimal places?
A: Use decimal places appropriate for your measurement precision. The calculator shows 4 by default.

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