Physics, Chemistry and Biology: Post your doubts here!

[Ibtizam]

my notes in physics, i feel as they are boring, maybe someone can tell me how to grasp the topic ? as once i repeat it, i then forget about it ?? plz maybe someone can help ?thnks

Use a revision guide !!!

 

[examkiller]

Use a revision guide !!!

But what about the details of each topic ? how to study those

 

[Ibtizam]

But what about the details of each topic ? how to study those

Use Notes ## Igcse Thread

 

[Afzal1]

But what about the details of each topic ? how to study those

u either have to buy a textbook or rely on ur teacher as for me i use (complete physics by Stephen pople) which covers excellently everything necessary for IGCSE

 

[Killer_555]

i have a question: igcse physics paper 6 winter 2005 question number 2(a). Its a diagram... can someone please make it and help me with it... moreover in paper 6 they constantly ask us to place a voltmeter in a parallel circuit to measure the voltage of two bulbs that are parallel to each other. How am i supposed to place the voltmeter ?

 

[examkiller]

Guys, what is a solenoid ?
Is there a difference between magnitude vs voltage ?
for emi, do they mean about a transformer or motor ?
for emi, what is its apparatus ? is a ac motor an emi or are they the ones that magnet and coil, hooked to a meter ?
For drawing transformer in exam, how many coils should i put on seconday coil ( output ) to show that it is a stepdown transformer ?
For transformer question : they say ''' what is the energy output in 30s '' any tips to how to solve this
and another question. How the input voltage is changed to an output voltage ? do i say about the primary coil is alternating, goes to core, then to secondary ?????
And what is the Primary coil exactly ? An incoming voltage vp, connected across the coil OR do i say primary coil has and alternating current, an electromagnet, produces alternating magnetic field ? thnks

 

[examkiller]

any one ?

 

[inquisitiveness]

for a step down,the coils should always be less thn the primary.
take the simplified ratio of the no.of coils written

 

[examkiller]

wh

for a step down,the coils should always be less thn the primary.
take the simplified ratio of the no.of coils written

what if there are no numbers of coil, they wrote. draw a transformer with the 240v ac, 12v. ? so should i put like more coils on 1 side, then the other for i.e 5=2 ?

 

[Nita Mahajan]

wh what if there are no numbers of coil, they wrote. draw a transformer with the 240v ac, 12v. ? so should i put like more coils on 1 side, then the other for i.e 5=2 ?

See, if you want more output voltage than the voltage given in the primary coil, then the number of turns of coil on the secondary coil would be greater than the primary coil.
However if you want lesser output voltage than the voltage provided in the primary coil, then the no. of turns on secondary coil would be lesser that the no of turns on the primary coil.

There is a formula - V2/V1=n2/n1 , where V2 stands for output voltage, V1 stands for input voltage, n2 stands for no. of turns on secondary coil and n1 stands for no. of turns on primary coil. Using the equation, you can find any value which you want.

 

[Afzal1]

Guys, what is a solenoid ?
Is there a difference between magnitude vs voltage ?
for emi, do they mean about a transformer or motor ?
for emi, what is its apparatus ? is a ac motor an emi or are they the ones that magnet and coil, hooked to a meter ?
For drawing transformer in exam, how many coils should i put on seconday coil ( output ) to show that it is a stepdown transformer ?
For transformer question : they say ''' what is the energy output in 30s '' any tips to how to solve this
and another question. How the input voltage is changed to an output voltage ? do i say about the primary coil is alternating, goes to core, then to secondary ?????
And what is the Primary coil exactly ? An incoming voltage vp, connected across the coil OR do i say primary coil has and alternating current, an electromagnet, produces alternating magnetic field ? thnks

2) EMI is only for a transformer bcoz the rate at which the magnetic field lines are cut by the current carrying conductor an induced emf is produced since we are turning the coil inside the magnets.
3)for emi
one apparatus for a current carrying conductor in a magnetic field which has a voltmeter connected or a galvanometer.
other of a coil in a magnetic field with has which has a voltmeter connected or a galvanometer.
4) the number of turns on the secondary coil should be lesser than the primary coil.
5)Use the formula (E=P*T) calculate power first and then multiply with the time.
6) Alternating current is supplied to the primary coil which produces an alternating magnetic field around the primary coil
and the iron core, this alternating magnetic field induces an alternating voltage in the secondary coil.

 

[examkiller]

tha

2) EMI is only for a transformer bcoz the rate at which the magnetic field lines are cut by the current carrying conductor an induced emf is produced since we are turning the coil inside the magnets.
3)for emi
one apparatus for a current carrying conductor in a magnetic field which has a voltmeter connected or a galvanometer.
other of a coil in a magnetic field with has which has a voltmeter connected or a galvanometer.
4) the number of turns on the secondary coil should be lesser than the primary coil.
5)Use the formula (E=P*T) calculate power first and then multiply with the time.
6) Alternating current is supplied to the primary coil which produces an alternating magnetic field around the primary coil
and the iron core, this alternating magnetic field induces an alternating voltage in the secondary coil.

thanks, youve really helped me as i was a bit confused. But is the last question, was it correct of how i wrote it or is it wrong ?

 

[Afzal1]

could u repeat the question it is unclear

 

[examkiller]

""And what is the Primary coil exactly ? An incoming voltage vp, connected across the coil OR do i say primary coil has an alternating current, an electromagnet, produces alternating magnetic field ?""
this one i am confused about, was i right about it or wrong ? thnks

 

[Afzal1]

the answer would be An incoming voltage vp, connected across the coil

 

[Bobby Jing]

Can somebody please explain this question to me?
"A car travelling within the town speed limit, at 13 m/s, hits a brick wall. For a passenger without a seat belt, this is like failing from the top of a house of height h metres. Find the value of h. (Houses are about 7m high)"

 

[Ijlal Amir]

Could Someone Be kind enough to tell me where i can get a thorough explanation of Forces such as air resistance , gravity i dont know the exact name of the subject , i think its moving bodies

 

[deltasierra]

Help with chemistry problem?
4.2 g of cerium reacted with oxygen to form 5.16 g of an oxide of cerium. Complete the following to determine the formula of this oxide.
(a) Number of moles of cerium atoms used
(b) Mass of oxygen that reacted
(c) Number of moles of oxygen atoms in oxide
(d) Ratio by moles of cerium atoms to oxygen atoms
(e) Formula of this oxide of cerium is ………

 

[inquisitiveness]

can someone please explain me the earthing thing related to induced spheres.
When do the electrons escape TO earth from sphere and when do they MOVE UP FROM earth to sphere?

 

[Ibtizam]

Help with chemistry problem?
4.2 g of cerium reacted with oxygen to form 5.16 g of an oxide of cerium. Complete the following to determine the formula of this oxide.
(a) Number of moles of cerium atoms used
(b) Mass of oxygen that reacted
(c) Number of moles of oxygen atoms in oxide
(d) Ratio by moles of cerium atoms to oxygen atoms
(e) Formula of this oxide of cerium is ………

Nyc
I need help too similar ^^^
Plz anyone answer this ^^