Dylan has made two different chemical batteries for a physics project. He is measuring how much voltage the batteries each produce. The first battery produces 3.12 volts, and the second battery produces 2.8 volts. Using the correct number of significant figures, how much greater was the voltage produced by the first battery, compared to the second?

Question

0.32 volts

0.320 volts

0.3 volts

0.3200 volts

Answer 1

To find the difference in voltage produced by the two batteries, we subtract the voltage of the second battery from the voltage of the first:

\[ 3.12 , \text{volts} - 2.8 , \text{volts} = 3.12 , \text{volts} - 2.80 , \text{volts} \]

Now, performing the subtraction:

\[ 3.12 - 2.80 = 0.32 , \text{volts} \]

Next, we need to consider significant figures in our result. The first battery's measurement (3.12 volts) has three significant figures, while the second battery's measurement (2.8 volts) has two significant figures. When performing subtraction, the result should be reported with the same number of decimal places as the measurement with the least number of decimal places, which is 2.8 volts (1 decimal place).

Since our calculation (0.32 volts) has 2 decimal places, it matches the requirement. Thus, the result, written with the correct number of significant figures, is:

0.32 volts

So, the correct answer is:

0.32 volts