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Is it question 12 intopic Electronics, CRO? (D03/P2/Q9)
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- Thread starter xhizors
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alright Usman i got ur question (the soil one)..
LDR = light dependent resistance means R is inversely proportional to light asan zaban mai resistance ki resist karnai taqat gir jati hai jaisai hi light around it barjati hai (or gorai is cheez ko sensor kehtai hai bewaqoof banatai hai
) in coclusion current will increase as resistance will decrease what u say ?? proportionality ab now in question
first term high in NOR gate what does this mean (all signal current bla bla transmit in only two stuff in computer terminology 0 and 1 ascii codes phy term high low chem term +ve and -ve electrons) for the sake of simplicity terms ko un kai subject mai hi rehnai daina bhai warna bluder well yar a(i) ki mai khaniya nhe karsakta i m little bit confuse in it i'll tell u by tommorw but now here a(ii) as their is dark resistance will be high causing less or no current to flow which means at A their would be 0 value in the dark
(b) truth table before telling u the answer i'll like to tell u about some info regarding NOR gate, what does OR means Addition
simply NOR means inverse of addition and plz Note (in gates 1+1 will always be 1) so what will be the input summition ans will be inverse like if sum is 1 than 0 will be the answer i guess u can now complete it by ur self
(c) (i) it is written above in ques that nor gate is high than pump is on now u can by urself answer it what u say (halwa haina) hint ans 1 lana hai
(c) (ii) (hint) 0 + 0 kya hoga ?? ans related to practical term
hopes this helps
pray for me for an outstanding result
LDR = light dependent resistance means R is inversely proportional to light asan zaban mai resistance ki resist karnai taqat gir jati hai jaisai hi light around it barjati hai (or gorai is cheez ko sensor kehtai hai bewaqoof banatai hai
) in coclusion current will increase as resistance will decrease what u say ?? proportionality ab now in questionfirst term high in NOR gate what does this mean (all signal current bla bla transmit in only two stuff in computer terminology 0 and 1 ascii codes phy term high low chem term +ve and -ve electrons) for the sake of simplicity terms ko un kai subject mai hi rehnai daina bhai warna bluder
well yar a(i) ki mai khaniya nhe karsakta i m little bit confuse in it i'll tell u by tommorw but now here a(ii) as their is dark resistance will be high causing less or no current to flow which means at A their would be 0 value in the dark(b) truth table before telling u the answer i'll like to tell u about some info regarding NOR gate, what does OR means Addition
simply NOR means inverse of addition and plz Note (in gates 1+1 will always be 1) so what will be the input summition ans will be inverse like if sum is 1 than 0 will be the answer i guess u can now complete it by ur self
(c) (i) it is written above in ques that nor gate is high than pump is on now u can by urself answer it what u say (halwa haina) hint ans 1 lana hai
(c) (ii) (hint) 0 + 0 kya hoga ?? ans related to practical term
hopes this helps
pray for me for an outstanding result
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@abcde: yeah the xact same one but PLEASE DO EXPLAIN WHY THE HELL IT ISNT IN THE PAST PAPERS OF XTREME :| :O
:| :O
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How will you write in words the answers to these questions... I have basic concepts about this stuff too yaar... :|
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AoA!
(a)(i) Note before: why do they say that you should not touch the switch of an electrical appliance with wet hands? That’s because damp conditions increase the chances of getting an electric shock. This is due to the fact that water has low resistance and so allows electric current to pass through it.
Conversely, when the soil is dry, it has HIGH resistance, allowing minimum or no current to pass through Input B. When current is low, so is the potential difference across input B, so the logic state (which depends on voltage) of Input B is low when the soil is dry.
(ii) Input A is directly connected to an LDR. When light intensity increases (bright light), its resistance decreases, allowing more current to pass through input A. So the potential difference in Input A is also high (more current => more p.d.) So the logic state is high in bright light. The reverse applies for dark.
(b) A NOR gate is the reverse of an OR gate so just recall the OR gate outputs at the given inputs and reverse them. In this case, the Output Q will be 1, 0, 0 and 0, respectively.
(c. (i) The water pump can only get on if Output Q is on, that is, 1. Read off the values from your truth table which make Output Q 1. The Input A is 0, the Input B is 0 and the Output Q is 1.
(ii) Recall part (a) here. Both inputs A and B need to be 0. The logic state of input B is low (near 0) when the soil is dry and the logic state of input A is low (near 0) when it is dark.
(d) The concept of a potential divider is tested here. Since the resistance of R1 is increased, the resistance of the LDR needs to be much greater so that the input A is low. If you require a greater resistance that means light intensity must be low. So less light is required for the pump to switch on and the light level would be darker.
Hope this helps!
(a)(i) Note before: why do they say that you should not touch the switch of an electrical appliance with wet hands? That’s because damp conditions increase the chances of getting an electric shock. This is due to the fact that water has low resistance and so allows electric current to pass through it.
Conversely, when the soil is dry, it has HIGH resistance, allowing minimum or no current to pass through Input B. When current is low, so is the potential difference across input B, so the logic state (which depends on voltage) of Input B is low when the soil is dry.
(ii) Input A is directly connected to an LDR. When light intensity increases (bright light), its resistance decreases, allowing more current to pass through input A. So the potential difference in Input A is also high (more current => more p.d.) So the logic state is high in bright light. The reverse applies for dark.
(b) A NOR gate is the reverse of an OR gate so just recall the OR gate outputs at the given inputs and reverse them. In this case, the Output Q will be 1, 0, 0 and 0, respectively.
(c. (i) The water pump can only get on if Output Q is on, that is, 1. Read off the values from your truth table which make Output Q 1. The Input A is 0, the Input B is 0 and the Output Q is 1.
(ii) Recall part (a) here. Both inputs A and B need to be 0. The logic state of input B is low (near 0) when the soil is dry and the logic state of input A is low (near 0) when it is dark.
(d) The concept of a potential divider is tested here. Since the resistance of R1 is increased, the resistance of the LDR needs to be much greater so that the input A is low. If you require a greater resistance that means light intensity must be low. So less light is required for the pump to switch on and the light level would be darker.
Hope this helps!
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Hey guys how can you tell if a metal clamp is horizontal above a bench with a spirit level???
By the way whats a spirit level?(taken fron Nov 10 p4 ms). Thanks in advance
By the way whats a spirit level?(taken fron Nov 10 p4 ms).
Thanks in advance
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workaholic said:Hey guys how can you tell if a metal clamp is horizontal above a bench with a spirit level???
By the way whats a spirit level?(taken fron Nov 10 p4 ms).
An instrument to check that the surface is horizontal or not... Google it then you will get its answer...
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@abcde: you are saying that (more current => more p.d.) but in some place it is like more voltage means more resistance :S so if resistance is more how more current is passing :|
And in this question no reference is to be given to current? I mean how it flows its direction etc? ??
And in this question no reference is to be given to current? I mean how it flows its direction etc? ??
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Usman17 said:
You can compare current and potential difference only when resistance is constant. Similarly, you can compare voltage and resistance when current is constant. One value is always constant, which enables you to compare the remaining two values of the equation R = V/I. More current => more p.d. when resistance is constant and more voltage means more resistance when current is constant. Clear?
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hey smeone tell me abt the colours of different precipitates???..
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For aluminium, calcium, zinc and lead its white... Copper blue, iron 2nd green, iron 3rd brown...
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thnx captain.....
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In the electrolysis of aqueous sodium chloride which gas will be given off on the anode???
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Why did you post the same question in two different threads?
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so that someone could answer it in any thread.......
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Check the other thread, Muhammad Talha. I think it's oxygen.
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Heyy can anyone pls solve ques 6 of this chem atp paper..i ll be really grateful..thanks
http://www.xtremepapers.me/CIE/Cambridg ... _qp_42.pdf
http://www.xtremepapers.me/CIE/Cambridg ... _qp_42.pdf