Lab Report #4

Can't figure out the format for the first part of question 9... anyone?

Nevermoind, got it...

For number 1 they are asking us to give the Kinetic Energy for the combined masses...

when I put KE = (.5)(M+m)(v^2) into maple TA it tells me that the answer is wrong.. am I plugging this in incorrectly?

thanks!

Does any one know the format for this question?
This is what I am entering... I've tried it a hundred different ways.

(Deltad/d)*d

please help!!

For number 1 type in this
.5*(m+M)*(v^2)
and it will be correct

and for number 10 the answer is
(Deltad/d)*v

For question 8, my value for d is .0250... how do we get delta d?

can anyone help me out.. im having so much trouble just starting off the table 2 i cant figure out how to find PE or KE

KE = (.5)*(M+m)*(v^2)

PE = -(m)*(g)*(h)

for question 8 ... the answer for Deltad is 0.00005 it was actually written in the lab somewhere.. this number is the same no matter what your d is

Does anyone know how to get the expected slope in question #24??

how to you solve for delta PE. I have used the eqn in number 13 both with and without multiplying PE. Any ideas?

These are my numbers:

deltam=.0002
m=.02
deltah=.003922
h=.0255
PE for the first one is -.005003

is delta h the same number as delta h calculated in problem 12? (i thought it was)
Is h the difference from say h2-h1? That way you have a different h for every row... right?

Very lost. Thank u

expected slope is -1...

how do you get the ratio in question 25 i did the math that they explain but im getting it wrong.

my slope of my best fit line was -1.05 and the error was 0.03

I did (-1.05 - -1)/.03 =-1.667

I tried it both neg and positive...

any help??

for question 6: What are the values of N, Nd, and delta Nd? im not getting it right

.. and every time i change my answer to question 6 my answer to question 8 becomes wrong :-x help

N = # of tape-blank pairs = 10
Nd = the measured length of the 10 tape-blank pairs (mine was .254 m, yours should be around that)
DeltaNd = sqrt((DeltaM)^2)+(DeltaM)^2)
= sqrt((.001^2)+(.001^2))
= .0014
(To get DeltaNd, you first have to estimate the absolute error for the length of 10d, I estimated .001 m, but yours might be different so you can just substitute your your value for the absolute error into the equation above)

In order to get both #6 and #8 correct,you have to make sure your values for #6 are correct because the values in both questions are connected to each other

For the questions where we enter in our own values for delta PE and KE... im only getting the first answer correct and each answer after is coming up wrong..

KE is just 1/2(M+m)v^2... where 1/2(M+m) is the same for each and all that changes is the v^2.. right?
and for the delta PE equation.. the only thing different in each equation is the value of PE?

My 10d=.253m
d=.0253m
delta 10d=.001
dela d=.0001?m how is this wrong???? i keep getting tht marked wrong

your answers are correct, i did the same thing for mines, and it is correct- maybe you're entering something else wrong?

i have no idea what do i need to put it for the question

does anyone else get a slope of ~ -1.8? is that wrong...? its because u multiply by .5 for KE...so ure dividing by 1/2 which makes the slope close to -2 even though its suppose to be -1
#24
Guest

iant it suppose to be -1 only if u are graphing PE vs KE and not PE vs gammaKE?

I'm a little confused with number 13. What would be the equation? Is it something dealing with the equation (7) in the error manual?

I put in sqrt(Deltam^2+Deltah^2) and it comes out wrong, is there something missing here???

I can see that there are lots of questions about this lab. In case you are not yet aware of it there is also a discussion going on over on the official help blog:

This seemed not to appear in the last post so I am posting it again.