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because fusion reaction requires very large temperatures to initiate and these temperatures are only usually seen in sun and stars etc
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Biology; Chemistry; Physics: Post your doubts here!
- Thread starter scouserlfc
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according to the formula, pressure = force/area. If force is constant, as in the question, we can deduce that pressure will be inversely proportional to area. So if the area increases, the pressure would decrease. So the ans should be d.
It should NOT be C because of inversely proportional graph.
http://www.google.com.pk/search?q=inversely proportional graph&tbm=isch&tbo=u&source=univ&sa=X&ei=HpOhUdGlBdG3hAe3roCYDg&ved=0CCwQsAQ&biw=1366&bih=667
Proportional graph has a straight line but inversely prop. does not.
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nuclei are positively charged, `as a result they repel each other. A large amount of thermal energy is required so that the kinetic energy overcomes this repelling force
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they are positively charged. as like charges repel so a huge amount of energy is needed
how does he know his marks, they dont show the papers
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he had rechecked his papers. after rechecking they send the answer booklet , mark sheet, q paper, and examiner report for that particular student's paperhow does he know his marks, they dont show the papers
but i didnt receive any of those in rechecking, maybe its just when ur grade gets changed
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yes his grade was changed frm A to A*. they even sent the money back.
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how does he know his marks, they dont show the papers
They do send the percenile to the schools who ask for them (for school level prizes/tops)
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http://papers.xtremepapers.com/CIE/Cambridge International O Level/Physics (5054)/5054_s12_qp_12.pdf....Q 12..how is the answer B?
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PLEASE HELP ME WITH THIS:
You have been given two identical(same colour, same size) pieces of metal. From there one is a magnet and other is a magnetic material. You have to describe a method to show which one is the magnet and which one is the magnetic material. Given that you can't have a string or any other things just the metal pieces.
You have been given two identical(same colour, same size) pieces of metal. From there one is a magnet and other is a magnetic material. You have to describe a method to show which one is the magnet and which one is the magnetic material. Given that you can't have a string or any other things just the metal pieces.
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bring near the two poles of magnet to the pieces , already held with a string. if it is magnet then it will move backward with one pole and come forward with another pole. if it is magnetic it will come forward to the magnet regardless of pole
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i am really sorry...i typed the question wrong. it shud be that you cannot have a string or other things. now please answer.
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The thing is that how do you that what u are bringing near the other is a magnet or not..... since u a only have the two things, they would attract in any case, so u cant differentiate!!!
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Are u sure thats the entire question??? Or can u at least tell the year and question if its a past paper question.....
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bring a magnet to each of the metals, the object which shows repulsion is a magnet while other is magnetic material
0 The background count rate in a laboratory is 10 counts/min.
The measured count rate from a radioactive source is 410 counts/min, which includes the
background.
The half-life of the source is 5 days.
What is the measured count rate after 15 days?
A 10 counts/min
B 50 counts/min
C 60 counts/min
D 110 counts/mi
The measured count rate from a radioactive source is 410 counts/min, which includes the
background.
The half-life of the source is 5 days.
What is the measured count rate after 15 days?
A 10 counts/min
B 50 counts/min
C 60 counts/min
D 110 counts/mi
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Background count = constant = 10 counts/min.
So, Radioactive source count = 400 counts/min.
After three half lives, the radioactive source count = 400/8 = 50 counts/min.
After 15 days, the count rate = 50 + 10 (b.c) = 60 counts/min. C.
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i think it is C