Question

Question 1

A group of students is told to use a meter stick to find the width of a physics lab room. They reported 6 independent measurements: 4.402 m, 4.217 m, 4.345 m, 4.925 m, 4.372 m, 4.289 m. How should they report their best estimate? (note: don’t forget to look for outliers and any extra decimal places)

Group of answer choices

W = (4.33 ± 0.03) m

W = (4.325 ± 0.073) m

W = (4.43 ± 0.25) m

W = (4.425 ± 0.104) m

Question 2

A student measures the length and width of a table and writes down the result as L = 1.786 ± 0.004 m; W = 0.925 ± 0.002 m. What is the area of the table? ( note: the area is the product of length and width for a rectangular table; recall quadrature method for uncertaintes)

Group of answer choices

.652 ± 0.006 m²

1.652 ± 0.005 m²

1.65205 ± 0.006 m²

1.65205 ± 0.00514 m²

Question 3

( Use this experiment to answer next four questions)

A group of students performs a tennis ball drop experiment to determine the acceleration of the falling ball. They measure the time and height of the fall and report the data as:

h = 6.25 ± 0.15 m, t = 1.24 ± 0.06 s. They use equation a = 2h/t² to determine average acceleration and uncertainty. What is the result for the acceleration in terms of unit m/s²?

Group of answer choices

8.1 ± 0.8 m/s²

8.1 ± 0.1 m/s²

8.13 ± 0.81 m/s²

8.0 ± 0.1 m/s²

Question 4

Acceleration of free-fall near the earth has a known value of 9.8 m/s². Based on the experiment described in the last question suppose the group got the acceleration of the falling tennis ball as 8.2 ± 0.9 m/s². What can be said about the result?

Group of answer choices

None of the above explanations make sense.

The result agrees with known value 9.8 within the uncertainty.

The result doesn’t agree with the known value within the uncertainty.

The result is lower. There must be mistake on either height or time measurement.

Question 5

What quantities were most helpful while comparing the acceleration with the known g in the above example?

Group of answer choices

The difference between height and time

How the human error was accounted for

The difference between the two values

The difference between two values compared to uncertainty

Question 6

The uncertainty in the above measurement seems high (0.9/8.2 = 11%). What one suggestion you could give to improve the result

Group of answer choices

Time and height contribute an equal amount to the uncertainty

Measure the time with higher precision as it contributes most to the uncertainty

Measure the height with more precision as it contributes most to the uncertainty

Question 7

The following two open-ended questions will be on almost all post-lab assessments. We will be grading based on your enthusiasm and honesty.

1) Please describe briefly what did you contribute to the group from the knowledge you already had from your major/minor/career? (10 pts)

2) What did you learn from the activities you did today to help you in your major/career? (10 pts)

Answer 1

1) take the mean od all the six measurements ,the value of mean is= (4.402+4.217+4.345+4.925+4.372+4.289)/6 = 4.425

So the option matching with value is the D option

2) percentage error in L = (0.004/1.786)*100=0.22%

Percentage error in W = (0.002/0.925)*100= 0.21%

Total percentage error = 0.43%

Area of rectangle = L*W = 1.786*0.925 = 1.65205

Error in area = 1.65205*043% = 0.007

So the accurate/ approximate ans is C option

3))

On calculating the acceleration = 2h/t*t = 2*6.25/1.24*1.24 = 8.129 = 8.13

now error in acc = 8.13 *percentage error in acceleration

percentage error in acc = 2.4+2*4.83=12.06%

Error in acc= 8.13*12.06%=0.9

so the correct/approximate option is c option

4))))

the result is lower,there must be mistake on either height and time measurements