PHYS 261 MOST ASKED QUESTIONS AND 100%
CORRECT ANSWERS
(Exp 1)A cell in an Excel spreadsheet contains $A$5. What does it mean?
The cell is fixed
(Exp 1)Which type of chart in EXCEL will actually plot the point at its
Cartesian coordinates?
scatter chart
(Exp 1)What is the Solver used for? (pick the best answer)
minimizing or maximizing a cell by varying other cells
(Exp 1)To run a macro in EXCEL, you may need to first click on.....?
the view tab and then click on the macro button.
(Exp 1)Before the lab template will let you exit from EXCEL, according to
step 21, you must...
1) enter your name in the designated area of the spreadsheet
2) enter your section number in the designated area of the spreadsheet
3) save the file using the gray save button in the body of the spreadsheet
(Exp 2)"1/3" rule to determine the uncertainty ∆x
Error is 1/3 of the smallest unit
(Ex: ruler in mm, error=1/3mm)
(Exp 2)estimate
sum of values/# of values
(Exp 2)The smallest increment the scale can display is 0.1 g and thus the
uncertainty ∆M in a measurement of mass would be about
0.033 g
(Exp 2)Using the ruler, and without using the vernier calipers, estimate
how precisely you can measure the length of one of the sides of one of the
blocks.
To the nearest mm with an error of 1/3mm
(Exp 2)Volume error
∆V =V*sqrt((∆c/c)^2 + (∆b/b)^2 + (∆a/a)^2)
(Exp 2)Density error
∆ ρ =ρ sqrt((∆V/V)^2 + (∆M/M)^2)
(Exp 2)Mean error
, ∆〈x〉=∆x/sqrt(N)
(Exp 2)χ2
=∑((xi-xtheory)/∆xi)^2
(Exp 2)Determining if values are consistent
are within 2 error bars from the accepted value
(Exp 2)Density consistent value
measured and accepted density should differ by no more than twice the uncertainty.
(Exp 2)"two-sigma rule"
if your data point is no more than two error bars from the accepted value then the
disagreement is not significant
(Exp 2)reduced χ2 should equal (blank) for good fit
1
(Exp 2)reduced χ2 eqn
χ2/v
(Exp 2)Degrees of freedom (v)
N-α (where N is the number of measurements and α is the number of fitting
parameters used to find the theoretical value from the data)
standard deviation
propagation of errors equation
∆f=sqrt(sum((df/dx)*∆x)^2))
(Exp 3)tilt angle of the air-track
theta= invsin(added height/length of track)
(Exp 3)position of cart vs time
x=0.5gsing(theta)t^2v0*t+x0
(Exp 3)Force of cart
Fx = Mgsin(θ)
(Exp 3)acceleration of cart
ax=gsin(θ)
(Exp 3)The ranger measures the position by...
emitting an ultrasonic pulse
CORRECT ANSWERS
(Exp 1)A cell in an Excel spreadsheet contains $A$5. What does it mean?
The cell is fixed
(Exp 1)Which type of chart in EXCEL will actually plot the point at its
Cartesian coordinates?
scatter chart
(Exp 1)What is the Solver used for? (pick the best answer)
minimizing or maximizing a cell by varying other cells
(Exp 1)To run a macro in EXCEL, you may need to first click on.....?
the view tab and then click on the macro button.
(Exp 1)Before the lab template will let you exit from EXCEL, according to
step 21, you must...
1) enter your name in the designated area of the spreadsheet
2) enter your section number in the designated area of the spreadsheet
3) save the file using the gray save button in the body of the spreadsheet
(Exp 2)"1/3" rule to determine the uncertainty ∆x
Error is 1/3 of the smallest unit
(Ex: ruler in mm, error=1/3mm)
(Exp 2)estimate
sum of values/# of values
(Exp 2)The smallest increment the scale can display is 0.1 g and thus the
uncertainty ∆M in a measurement of mass would be about
0.033 g
(Exp 2)Using the ruler, and without using the vernier calipers, estimate
how precisely you can measure the length of one of the sides of one of the
blocks.
To the nearest mm with an error of 1/3mm
(Exp 2)Volume error
∆V =V*sqrt((∆c/c)^2 + (∆b/b)^2 + (∆a/a)^2)
(Exp 2)Density error
∆ ρ =ρ sqrt((∆V/V)^2 + (∆M/M)^2)
(Exp 2)Mean error
, ∆〈x〉=∆x/sqrt(N)
(Exp 2)χ2
=∑((xi-xtheory)/∆xi)^2
(Exp 2)Determining if values are consistent
are within 2 error bars from the accepted value
(Exp 2)Density consistent value
measured and accepted density should differ by no more than twice the uncertainty.
(Exp 2)"two-sigma rule"
if your data point is no more than two error bars from the accepted value then the
disagreement is not significant
(Exp 2)reduced χ2 should equal (blank) for good fit
1
(Exp 2)reduced χ2 eqn
χ2/v
(Exp 2)Degrees of freedom (v)
N-α (where N is the number of measurements and α is the number of fitting
parameters used to find the theoretical value from the data)
standard deviation
propagation of errors equation
∆f=sqrt(sum((df/dx)*∆x)^2))
(Exp 3)tilt angle of the air-track
theta= invsin(added height/length of track)
(Exp 3)position of cart vs time
x=0.5gsing(theta)t^2v0*t+x0
(Exp 3)Force of cart
Fx = Mgsin(θ)
(Exp 3)acceleration of cart
ax=gsin(θ)
(Exp 3)The ranger measures the position by...
emitting an ultrasonic pulse
