Author Topic: Physics  (Read 1180 times)

Offline gaurav95

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Physics
« on: May 13, 2010, 06:38:19 am »
Can somebody solve the q 10
from both the papers.............The whole question  :) :) :) :)
I dont understand the m.s. also.......

Thanks in advance.......
« Last Edit: May 13, 2010, 06:43:23 am by gaurav95 »
If the sky is the limit, then what is space, over the limit?

Offline Vin

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Re: Physics
« Reply #1 on: May 13, 2010, 06:48:45 am »

post ur question here from now on ..

https://studentforums.biz/index.php/topic,6468.780.html

wait a min lemme see the q.

Offline Vin

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Re: Physics
« Reply #2 on: May 13, 2010, 06:56:46 am »

june 07
You should kno what is a thermistor .. a semi-conducting material which when temperature increases its resistance decreases .. resulting a fall in the p.d across R1 tht is the base emitter pd increases .. when it exceeds a certain amount the light is switched on ..

Offline gaurav95

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Re: Physics
« Reply #3 on: May 13, 2010, 07:02:32 am »
june 07
You should kno what is a thermistor .. a semi-conducting material which when temperature increases its resistance decreases .. resulting a fall in the p.d across R1 tht is the base emitter pd increases .. when it exceeds a certain amount the light is switched on ..
The 2nd q
If the sky is the limit, then what is space, over the limit?

Offline Vin

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Re: Physics
« Reply #4 on: May 13, 2010, 07:08:39 am »
nov 06

A - resistor
B -LDR or light dependent resistor
C - Transistor
D - Lamp

b) C

c) the lamp comes on when the LDR is in dark because more of battery pd being dropped across increased resistance (of LDR) which is greater than 0.6 V and less at A .. hence the base emitter pd increases as the base current and collector current

for these type of ques u need to kno the concept of potential divider very well .. sry to reply so late my nets bad .. =|

Offline gaurav95

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Re: Physics
« Reply #5 on: May 13, 2010, 08:26:19 am »
Thanks  alot
If the sky is the limit, then what is space, over the limit?