Question

1) 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 0.1800.180 amps, but he measures the current as 0.1730.173 amps. What is Roland's percent error? 2) Two objects have masses of 1.1551.155 kg and 0.220.22 kg, respectively. Using the correct number of significant figures, what is the sum of these masses? 3) Kwame is measuring the dimensions of a box he will be using in a coming experiment. He measures the dimensions of the box as 0.8850.885 meters wide 0.200.20 meters deep, and 0.750.75 meters tall. Using the correct number of significant figures, what is the volume of this box? please try to answer as many questions as you can, thank you.

Answer 1

Answer:

1)  3.9 %

2) 1,38 kg

3) 0.13 cubic meters

Explanation:

Part 1)

Calculated current = 0.180 amps

Measured current: 0.173 amps

percent error :   $\frac{0.180 - 0.173}{0.180} \,100=3.9$ %

Part 2)

mass1 = 1,155 kg

mass2 = 0.22  kg

Addition; 1.155 + 0.22 = 1 375 kg  which should be rounded to just two decimals according to the addition rules for uncertainties:

Answer : 1,38 kg

Part 3)

Volume = 0.885 x 0.20 x 0.75 cubic meters = 0.13275 cubic meters

Notice that the smallest number of significant figures among the set of dimension given is two. Therefore, our answer should be rounded to two significant figures. That is:

Volume = 0.13 cubic meters