Roland has built a circuit, and is using a device called an ammeter to measure how quickly electrical current is flowing through the circuit. He calculates that the current should be 0.180 amps, but he measures the current as 0.173 amps. What is Roland's percent error?

Question

3.89
0.00389
0.045
4.05
0.0389

Answer 1

To calculate the percent error, you can use the following formula:

\[ \text{Percent Error} = \left(\frac{\text{|Measured Value - Actual Value|}}{\text{Actual Value}}\right) \times 100 \]

In this case:

• Actual Value (calculated current) = 0.180 amps
• Measured Value = 0.173 amps

Now, plugging in the values:

\[ \text{Percent Error} = \left(\frac{|0.173 - 0.180|}{0.180}\right) \times 100 \]

Calculating the absolute difference:

\[ |0.173 - 0.180| = 0.007 \]

Now, substituting that back into the percent error formula:

\[ \text{Percent Error} = \left(\frac{0.007}{0.180}\right) \times 100 \]

Calculating the fraction:

\[ \frac{0.007}{0.180} \approx 0.03889 \]

Now, multiply by 100 to find the percent:

\[ 0.03889 \times 100 \approx 3.889 \]

Rounding to two decimal places gives:

\[ \text{Percent Error} \approx 3.89% \]

So the correct answer is 3.89.