HI! :( Im sorry to bother you guys but I need help on only these three questions. I'm not trying to cheat but these three are really confusing. This is the first time I've ever asked for help on the internet haha. Please don't be upset I promise this is the only time.
13. You measure the mass of a 0.500 kg (500 g) standard on your balance four times. The following measurements result: 498 g, 501 g, 499 g, 500 g. Which of the following best describes your balance? (Points : 3)
not precise and not accurate
not precise but accurate
precise and accurate
precise but not accurate
14. If a box has a length of 10.0 cm, a width of 15 cm, and a height of 5.0 cm, then what is its volume in m3?
(Points : 3)
7.5 × 104
7.5 × 103
7.5 × 102
750 × 102
15. What is the difference between 3.150 m and 2.006 m with the correct number of significant figures?
(Points : 3)
1 m
1.1 m
1.14 m
1.144 m
13. The balance is not very precise. A good quality balance should have a precision (readability) if 0.01 grams. It is fairly accurate (free of bias), since the mean is within a standard deviation of the actual value.
I am not sure what the person who asked the question considers accurate and precise. One could justify different answers here.
14. None of those choices is correct. You may have failed to put a sign on an exponent. The correct value is 750 cm^3 = 750*10^-6 m^3 = 7.5*10^-4 m^3)
They asked for the answer in cubic meters.
15. 1.144 m
Hello! I'm happy to help you with these questions. Don't worry, I'm here to assist you, and there's no need to apologize.
Let's dive into each question and find the answers:
13. This question asks about the precision and accuracy of your balance. Precision refers to how close the measurements are to each other, while accuracy refers to how close the measurements are to the true value. From the given measurements (498 g, 501 g, 499 g, 500 g), we can see that they are not consistently close to each other or the true value. The measurements vary by a couple of grams, and none of them are exactly 500 g. Therefore, the best description for your balance is "not precise but accurate."
14. To find the volume of the box in cubic meters, we need to convert the given dimensions to meters. The length is 10.0 cm (which is already in centimeters), the width is 15 cm, and the height is 5.0 cm. Since 1 meter is equal to 100 centimeters, we divide each dimension by 100 to convert them to meters.
Length: 10.0 cm = 10.0 / 100 = 0.10 m
Width: 15 cm = 15 / 100 = 0.15 m
Height: 5.0 cm = 5.0 / 100 = 0.05 m
Now, we can calculate the volume by multiplying the length, width, and height together:
Volume = 0.10 m * 0.15 m * 0.05 m = 0.0075 m³
The volume of the box is 0.0075 cubic meters. However, we need to choose the option that matches this value in scientific notation. 0.0075 can be written as 7.5 x 10^-3 in scientific notation. The option that matches this is "7.5 × 10^2."
15. To find the difference between 3.150 m and 2.006 m with the correct number of significant figures, we need to determine the least number of decimal places in both numbers.
3.150 m has three decimal places.
2.006 m has three decimal places.
Since both numbers have the same number of decimal places, we can subtract them directly:
3.150 m - 2.006 m = 1.144 m
The difference between 3.150 m and 2.006 m, with the correct number of significant figures, is 1.144 m.
I hope this helps! Let me know if you have any further questions or if there's anything else I can assist you with.