1. What is Percent Error?

Percent error is a measure of how inaccurate a measurement is, compared to the true or accepted value. It's expressed as a percentage and is used to quantify the difference between experimental and theoretical values.

2. How Does the Calculator Work?

The calculator uses the percent error formula:

Where:

• \( Experimental \) — The measured or observed value
• \( Theoretical \) — The true, expected, or accepted value

Explanation: The formula calculates the absolute difference between the experimental and theoretical values, divides by the absolute theoretical value, and converts to a percentage.

3. Importance of Percent Error Calculation

Details: Percent error is crucial in scientific experiments and measurements to assess the accuracy of results and compare them to expected values or standards.

4. Using the Calculator

Tips: Enter both experimental and theoretical values. The theoretical value cannot be zero (division by zero is undefined). Values can be positive or negative.

5. Frequently Asked Questions (FAQ)

Q1: What is a good percent error value?
A: This depends on the field, but generally, <5% is excellent, <10% is good, and >20% may indicate significant issues.

Q2: Can percent error be negative?
A: No, the absolute value in the formula ensures percent error is always positive or zero.

Q3: What's the difference between percent error and percent difference?
A: Percent error compares to a known value, while percent difference compares two experimental values.

Q4: Why use absolute values in the formula?
A: Absolute values ensure the error is always expressed as a positive quantity, regardless of direction.

Q5: How does this relate to standard deviation?
A: Percent error measures accuracy (vs. a known value), while standard deviation measures precision (variation in repeated measurements).