Author Topic: URGENT QUESTION! No time left please guys ..  (Read 920 times)

Offline hols

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URGENT QUESTION! No time left please guys ..
« on: May 12, 2010, 08:40:35 am »
Physics May/June 2009 paper 3B
Section B, Question 6

It says (for the people who dont have it):

An engineer carried out an investigation to determine the Young modulus of a sample of a material.

(b) The engineer obtained three sets of data. The values for the Young modulus were 14.2, 14.7 and 15.1 GPa.

Determine the average value and state its uncertainty.
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The average value is 14.7, but what's the uncertainty ? And please elaborate how did you calculate it?

Offline T.Q

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Re: URGENT QUESTION! No time left please guys ..
« Reply #1 on: May 12, 2010, 08:51:25 am »
range /2

(max value - min value)/2

(15.1-14.2)/2=0.45

and the uncertainty always take it to one significant figure

so uncertainty = +-0.5 
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Offline abuelzouz

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Re: URGENT QUESTION! No time left please guys ..
« Reply #2 on: May 12, 2010, 09:10:15 am »
wt about last hour revision?

Offline Q80BOY

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Re: URGENT QUESTION! No time left please guys ..
« Reply #3 on: May 12, 2010, 09:15:29 am »
don't do last hour revision .. chill out .. grab a bite .. head to the exam refreshed and relaxed ;)

best of luck!!  :)
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Offline hols

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Re: URGENT QUESTION! No time left please guys ..
« Reply #4 on: May 12, 2010, 09:15:49 am »
Thank you so much ! +rep

Offline abuelzouz

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Re: URGENT QUESTION! No time left please guys ..
« Reply #5 on: May 12, 2010, 09:16:47 am »
yea i knw but i just want 2 make sure i covered everything..

wt did u study?

Offline halosh92

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Re: URGENT QUESTION! No time left please guys ..
« Reply #6 on: May 12, 2010, 06:30:50 pm »
nov 2009
paper 1 cie physics
Q6
Q21
Q26
Q27
Q29
thxx alooot
By the way does anyone think that this paper is hard or is it just me??
:S :-\
« Last Edit: May 12, 2010, 09:06:23 pm by halosh92 »
everyday we wake up is a miracle, then how do we say miracles dont happen?????