Physics, Chemistry and Biology: Post your doubts here!

[Princess Raven]

could u help me out wid the whole menstrual cycle including the hormones LH and FSH this part just dosent get into my mind

arent u done with bio??

 

[GorgeousEyes]

ok for this u just do 6v-2.4= 3.6v
then I4= 1.2+0.8= 2
r= 3.6/2
= 1.8ohms

THAAANKS !

 

[Ahmed Al Hilali]

5B Answered
11 b Because it is NPN transistor the current flow is from emitter to base and here you DON'T need a thermistor (This is for temperatures and here we don't have to note the temperature) Your question why don't we keep Variable resistor at b and LDR at A this has a lot to explain but lemme give it a go so when the light intensity decreases(becomes dark) the resistance increases for LDR and now when Resistance increases Voltage increases and we need a higher share of voltage at B not at A because we need the PD across the Base to e larger enough for the base current to switch on the collector-emitter current as when the large current flows from the collector to emitter the bulb will light and at A is has Less share of resistance from the power supply.
c- Themistor Hot and then Resistance decrease ad voltage decrease so this has to be placed at A this time to switch on the circuit Large voltage at B and low at A so that all about this
I really can explain you 10 a wordy

thanks a lot

 

[GorgeousEyes]

please Nov011 v.31 no.1 b ii

 

[GorgeousEyes]

Could i write in Nov011 2 a) Sun evaporates water from lake forming clouds that fall again as rain and they form river and this river is dammed to make a lake and water rushes from Lake to turn generators at the foot of the dame . PE--> Electric ?

 

[himanshu dave]

no

arent u done with bio??

 

[shafay haseeb]

can u tell me about diode and thermister and also transister!

 

[GorgeousEyes]

PLEASE 4 a) With drawing plzzz .

 

[ZaqZainab]

Thanks very much , but could u tell me please the thumb and the first and second finger usage . I am really confuse

The force(Thrust of the motion) is the Thumb
First fingure magnetic Field
The Current is the Center figure

 

[GorgeousEyes]

The force(Thrust of the motion) is the Thumb
First fingure magnetic Field
The Current is the Center figure

You are a life saver thank u

 

[GorgeousEyes]

Nov011 v.31 ,6) b and 7) b i and 9) b URGENTLYYY

 

[ZaqZainab]

please Nov011 v.31 no.1 b ii

this might help

 

[ZaqZainab]

Could i write in Nov011 2 a) Sun evaporates water from lake forming clouds that fall again as rain and they form river and this river is dammed to make a lake and water rushes from Lake to turn generators at the foot of the dame . PE--> Electric ?

The energy change would be better if you mention that P.E is first changed to Kinetic Energy when the water flows from the foot of the dame and then this KE is used to spin turbines to create electric energy this and the evaporation would let you score full marks

 

[ZaqZainab]

You are a life saver thank u

My pleasure got any more doubts?

 

[ZaqZainab]

Could i write in Nov011 2 a) Sun evaporates water from lake forming clouds that fall again as rain and they form river and this river is dammed to make a lake and water rushes from Lake to turn generators at the foot of the dame . PE--> Electric ?

and if you want a formal answer here "Energy from the sun evaporates water in the Earth’s oceans and rivers and draws it upward as water vapor. When the water vapor reaches the cooler air in the atmosphere, it condenses and forms clouds. The moisture eventually falls to the Earth as rain or snow, replenishing the water in the oceans and rivers and lakes. The rivers are dammed........

 

[oahmed64]

at the instant when the coil is vertical,the springy contacts do nit in fact make contact with the ends of the coil.
describe and explain what happens to the coil?
anyone?

 

[The Gooner]

hello, if i a get a 60-65 % in IGCSE Chemistry core is that considered a C? im really worried, thanks.

 

[oahmed64]

hello, if i a get a 60-65 % in IGCSE Chemistry core is that considered a C? im really worried, thanks.

thats an a or a*

 

[The Gooner]

So in Chemistry Core how much do i need to get in order to get a C?

 

[Mohammed salik]

Guys a Question plz: http://papers.xtremepapers.com/CIE/Cambridge IGCSE/Physics (0625)/0625_s12_qp_31.pdf Q11 b! In Gap A why cant u PuT Light Dependendant Resistor! Why should we put on Only in Gap B! Any Help Would Be Helpful, Thanx IN ADVANCE!!