wHAT ARE THE WAYS of reducing sample and random error???

[utsav156]

can anyone tell wHAT ARE THE WAYS of reducing systematic and random error???

 

[princesszahra]

to reduce random error
repeat the exp and take average of the values
keep the conditions constant like temp etc


to reduce systematic error
change the way of performing the exp like use burette instead of a dropper!

you can specifically ask me about any experiment
ill tell u abt it

 

[utsav156]

ty princess zahara
btw its gud to see ya back after a lng tym

 

[princesszahra]

ty princess zahara
btw its gud to see ya back after a lng tym

I come online everyday at XPF except for these 2 days!!

Tell me any specific question about with u want to know abt errors!

 

[utsav156]

ya i din saw u thats why?

ok now what is zero errors??
how can u reduce errors in wrongly calibrated scales
in thermometer
ruler and ammeters!!!!

 

[thunderingthunder]

ya i din saw u thats why?

ok now what is zero errors??
how can u reduce errors in wrongly calibrated scales
in thermometer
ruler and ammeters!!!!

It is the incorrect reading that you have on your instrument when it is measuring something that *you know* should read zero.
For example, if you have an Amp Meter (to measure electrical current, you close the measuring contacts on a metal wire. There is *no* current flowing in the circuit. And yet your instrument reads a number different than zero. That number is your Zero Error.You correct Zero Errors by pre-calibrating your instrument and adjusting all the readings of the future measurements that way.

 

[princesszahra]

ya i din saw u thats why?

ok now what is zero errors??
how can u reduce errors in wrongly calibrated scales
in thermometer
ruler and ammeters!!!!

zero error is that in which u have a value without actually using that instrument
like when u close the micrometer screw guage without anyting , u have a value of 0.03
this is zero error

to reduce random error in thermometer , ruler and other instruments
find the readings without the change involved and then add in the stubstance for which u want to measure a change
subtract the error from it!!
did u get it?

 

[utsav156]

ya i got it (almost )
umm i have juss attached a file can u plz chek it out
errr its question b realted sth with systematic errors

 

[utsav156]

the attachment!!!

 

[Amna]

a) micrometer screw gauge
b) i) close the micrometer fully, check that the reading on it's scale should be zero. (meaning check there's no zero error, which is an example of a systematic error)
ii) take at least three readings and obtain a mean values from them to use in further calculations.

 

[hassam]

take three readings around the circumference SPIRALLY....or along the length of wire and then take avg.....
http://www.xtremepapers.me/CIE/Internat ... 6_qp_2.pdf
see that LAMP question and tell me wats that fault ...

 

[Amna]

since the three lamps are similar, all three have resistance=15Ω. thus when both switches S2 and S3 are closed, the effective resistance should be 22.5Ω. however, the actual resistance is lesser so that means the current has found another path of less resistance, i.e. the lamp is shorted.

hope that makes sense...

Another way you can answer that is that there can only be two kinds of faults; either the current isn't flowing at all (= broken circuit = no contribution to the total resistance of the circuit) or the current is flowing but through another path. so if the circuit is broken (bulb is fused) the effective resisstance is 15 + 15 = 30Ω, which obviously doesn't work out. But if it is a short circuit, assume the short path has a resistance of say 0.005Ω which is like, almost negligible, but not quite so it's like what most wires usually have, so taking R=0.005Ω, the total R of B and C is 0.00999Ω. that in combination with the resistance of A gives R= 15.00999Ω which is approx 15Ω. that works out.

hope that helped

 

[hassam]

so lamp c is the shorted one ryt.,?

 

[princesszahra]

@ utsav
amna explained it right!

 

[Amna]

yeah C is the shorted one
lol thanks princess

 

[utsav156]

thanks amna!!!

 

[Amna]