Physics: Post your doubts here!

[Thelastmoment]

Guys do we have to wash the conical flask before performing the next titration in chem prac? ._.

Oh and you asked about the next titration of course wash it with distilled water you're provided with it, in the wash bottle, don't use tap water.

 

[anastasia grey113]

Guys do we have to wash the conical flask before performing the next titration in chem prac? ._.

yess

 

[selrey]

Kkk! Thankyou guys!

 

[Thelastmoment]

Out of curiosity though Anyone doing 34 Physics on the 30th?

 

[amina1300]

The cross-section of an Olympic-size swimming pool filled with water. It is not
drawn to scale. The density of the water is 1000kg m–3... Can someone explain how the answer is 3.4 KPa and not 3.5kPa. Q20 winter 2015 p12?

 

[Thelastmoment]

Okay so you have to use the Young Modulus thing:
Y.M= Stress/Strain; Stress= F/A and Strain=e/L
When combined gives you Y.M=FL /Ae
Use this;

Hope this helps.

 

[amina1300]

Okay so you have to use the Young Modulus thing:
Y.M= Stress/Strain; Stress= F/A and Strain=e/L
When combined gives you Y.M=FL /Ae
Use this;

Hope this helps.

Thankyou.

 

[Thelastmoment]

Thankyou.

No worries ^_^

Anything else?

 

[amina1300]

No worries ^_^

Anything else?

mj2014 p13 q 37 38

 

[Thelastmoment]

They have the February March 2017 released onto Dynamicpapers.com check the MCQs

 

[Awoudam]

https://papers.gceguide.xyz/A Levels/Physics (9702)/9702_w12_ms_11.pdf

Can you help me out with question 8

 

[amina1300]

If we take the coordinates from the top of the line and calculate gradient after ensuring units consistentency : 105 km/h into m/s by 105*1000/3600 -----》 grad = [ans/4] and we get D =7.3 rounded off to 2 s.f.

 

[amina1300]

http://papers.gceguide.com/A Levels/Physics (9702)/9702_w15_qp_13.pdf Q 37, 29,27,14

 

[janedoe]

In finding absolute error, do we divide least count of instrument by two? Or do we take the least count as absolute error?
E.g. In metre rule will absolute error be 1mm or 0.5mm for a single reading?

 

[janedoe]

The sig fig in raw t would be 4. So we should take sig fig in T^2 as 4 or 5..? Don't we usually take calculated values to 3 sig figs?
Any help would be appreciated.

 

[amina1300]

The sig fig in raw t would be 4. So we should take sig fig in T^2 as 4 or 5..? Don't we usually take calculated values to 3 sig figs?
Any help would be appreciated.

4 s.f

 

[amina1300]

In finding absolute error, do we divide least count of instrument by two? Or do we take the least count as absolute error?
E.g. In metre rule will absolute error be 1mm or 0.5mm for a single reading?

This was confusing for me too. Absolute error or absolute incertainty is the uncertainty in a measurement, which is expressed using the relevant units, 0.5mm is the estimated error ( least count/2) so you should take 1mm.

 

[Thelastmoment]

mj2014 p13 q 37 38

 

[janedoe]

This was confusing for me too. Absolute error or absolute incertainty is the uncertainty in a measurement, which is expressed using the relevant units, 0.5mm is the estimated error ( least count/2) so you should take 1mm.

Thank you.

 

[amina1300]

http://papers.gceguide.com/A Levels/Physics (9702)/9702_w15_qp_13.pdf Q 37, 15 , 9