Biology; Chemistry; Physics: Post your doubts here!

[funky brat]

Guys I need to know about magnification in bio! I want to know how to do it,how the questions propose we do it and everything related to it.Thankyou, help will be appreciated

You just need to state the magnification of the image using the formula image/ object.
Measure the length or width as per question requirement and the corresponding length of your image and then put these values into the formula. If the picture given in the paper has already been magnified, the magnification would have been stated use the formula Image/Object*magnification.
Always measure all the lengths in mm for accuracy.

 

[Jeed]

Could someone please tell me if the physics (syllabus onnly) can be revised in 4 days? Please reply asap. Is magnetism actually as difficult as it looks?

 

[Dream.Eater]

Can someone please tell me how to do part c of the ON 2012 Physics 5054 paper 42

 

[Dream.Eater]

Could someone please tell me if the physics (syllabus onnly) can be revised in 4 days? Please reply asap. Is magnetism actually as difficult as it looks?

I'm not sure how long it will take.Depend on how familiar you are with the syllabus.
And no magnetism isn't that hard. You just have to grasp a few laws and concepts..

 

[funky brat]

Could someone please tell me if the physics (syllabus onnly) can be revised in 4 days? Please reply asap. Is magnetism actually as difficult as it looks?

Yes, it can surely be revised in four days.
What I actually feel is magnetism is the easiest of all, at least the MCQs are much less technical as compared to those from other parts of the syllabus.

 

[funky brat]

Can someone please tell me how to do part c of the ON 2012 Physics 5054 paper 42

Kindly be more specific while asking.
I assume you're asking about part c of the last question. The normal drawn is wrong because the ray does not strike the mirror at angle of 90 to the surface infact it strikes the mirror at a different angle. Therefore the correct normal would be a tilted line that makes 90 angle with the prism.

 

[Dream.Eater]

Kindly be more specific while asking.
I assume you're asking about part c of the last question. The normal drawn is wrong because the ray does not strike the mirror at angle of 90 to the surface infact it strikes the mirror at a different angle. Therefore the correct normal would be a tilted line that makes 90 angle with the prism.

Oops. I'm extremely sorry what I meant was part c of the first question.
Sorry for t trouble.......

 

[funky brat]

Oops. I'm extremely sorry what I meant was part c of the first question.
Sorry for t trouble.......

Lol. Okay wait.

 

[asadalam]

Oops. I'm extremely sorry what I meant was part c of the first question.
Sorry for t trouble.......

Its because the dead space(space behind the 0 indicator on the ruler) would also be included if we place it on the bottom of the tray so the reading would be inaccurate.We can fix that by measuring the dead space and subtracting it from the ruler reading from the tray to get an accurate result.

 

[funky brat]

Oops. I'm extremely sorry what I meant was part c of the first question.
Sorry for t trouble.......

Its because the dead space(space behind the 0 indicator on the ruler) would also be included if we place it on the bottom of the tray so the reading would be inaccurate.We can fix that by measuring the dead space and subtracting it from the ruler reading from the tray to get an accurate result.

Sorry, forgot to reply.
He's right. There's a space before the zero which we always skip and start from zero while taking the readings, but in this case the ruler is placed below the liquid. So it can be measured separately and then subtracted from the total.

 

[Jeed]

Yes, it can surely be revised in four days.
What I actually feel is magnetism is the easiest of all, at least the MCQs are much less technical as compared to those from other parts of the syllabus.

Thank you for the reply. you are giving your exams in this session?

 

[Dream.Eater]

Its because the dead space(space behind the 0 indicator on the ruler) would also be included if we place it on the bottom of the tray so the reading would be inaccurate.We can fix that by measuring the dead space and subtracting it from the ruler reading from the tray to get an accurate result.

Sorry, forgot to reply.
He's right. There's a space before the zero which we always skip and start from zero while taking the readings, but in this case the ruler is placed below the liquid. So it can be measured separately and then subtracted from the total.

Thanks a ton!!

 

[funky brat]

Thank you for the reply. you are giving your exams in this session?

Yes, I'm appearing for six subjects this M/J.

 

[Mahnoorfatima]

There's this chemistry 5070 MJ 011 Last question part g : the last part of the paper . How do I solve it? Plus while drawing graphs, not for chemistry only but for bio aswell , Is it necessary that the graph should pass through the origin. Of course Im talking about linear graphs/the straight line ones! Please answer ASAP as I have loaaads of papers to do Inshaa Allah.
May Allah grant us all with extremely easy papers and loads of A*s! AMEEN.

 

[mohsina asif]

I need immediate help with physics ATP. PLEASE help me about how to use a set square theres this oct nov 2002 paper 6 first question. How do you arrange it with the ruler?

 

[mohsina asif]

You just need to state the magnification of the image using the formula image/ object.
Measure the length or width as per question requirement and the corresponding length of your image and then put these values into the formula. If the picture given in the paper has already been magnified, the magnification would have been stated use the formula Image/Object*magnification.
Always measure all the lengths in mm for accuracy.

What about when they have given a magnification with figure eg at the side of the picture of microscopic slide x100 and then we make an image, so we calcalutae the mag by drawing size/ object x100?

 

[funky brat]

What about when they have given a magnification with figure eg at the side of the picture of microscopic slide x100 and then we make an image, so we calcalutae the mag by drawing size/ object x100?

Not *100 all the time. It depends what the magnification of the picture is. You just have to multiply it by that number.

 

[Mahnoorfatima]

Steps involved in fractional distillation of air anyone??????????????

 

[Mahnoorfatima]

And how burnin of coal results in formation of acid rain

 

[funky brat]

There's this chemistry 5070 MJ 011 Last question part g : the last part of the paper . How do I solve it? Plus while drawing graphs, not for chemistry only but for bio aswell , Is it necessary that the graph should pass through the origin. Of course Im talking about linear graphs/the straight line ones! Please answer ASAP as I have loaaads of papers to do Inshaa Allah.
May Allah grant us all with extremely easy papers and loads of A*s! AMEEN.

No, linear graphs need not to pass through the origin, it is only the directly propotional ones. The difference between the linear and directly propotional graph is that in graph of load against stretch, the spring initially has some length so even if for an increase of 1 Newton force, there is an increase of 1 cm in length. So this is a linear relationship, directly proptional is when force is 0 length of spring is also zero.
And for the question part you should know that black colour is not only a good absorber of a heat but a good radiator as well and shiny surfaces are poor radiators of heat. Therefore the liquid in tube A would cool down more quickly than that in tube B. The shape of the curve would be like this.