Calculating Percentage Error for a Circular Disc with (10 +/- 0.2)cm Radius

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To calculate the percentage error for the circumference of a circular disc with a radius of (10 +/- 0.2) cm, the absolute error is determined to be 0.2 cm. The circumference formula is C = 2πr, leading to the need to apply the error propagation formula. The relevant equation for the absolute error in circumference is derived from the relationship between the circumference and radius. By substituting the values into the error equation, one can find the percentage error in the circumference calculation. This method effectively incorporates the radius's uncertainty into the final result.
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Homework Statement


A circular disc has a radius of (10 +/- 0.2)cm. Determine the percentage error in the determination of its circumference.

The Attempt at a Solution


I know that percentage error is found by absolute error divided by measurement x 100. The absolute error here is 0.2cm, and the measurement is 10cm. But what do I have to do with circumference?
 
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Have you used the error equation before?

If we want to work out the absolute error on C and C = 3A, then,

(error on C)^2 = ((dC/dA)*(error on A))^2

From memory i think it's that. So imagine the circumference is C and make an equation for it. You should be able to get it from that.
 
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