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Ayushi Aggarwal
Subject: Physics
, asked on 14/2/18
Question 37
Q.37.
In only one of the circuits given in Fig. 14.40, the lamp L lights . Which circuit is it ? Give reason for your answer.
[Delhi 2001 C]
Answer
1
Ayushi Aggarwal
Subject: Physics
, asked on 14/2/18
Ques_36
Answer
2
Manveen Kaur
Subject: Physics
, asked on 13/2/18
solve question 13
13.
Two metallic plates of equal length and thermal conductivity k
1
and k
2
are put together as shown in fig. The cross-sectional area of each rod is A. Find the equivalent thermal conductivity of composite rod. Ans : (k
1
+ k
2
)/2
Answer
1
Chaitanya Kapoor
Subject: Physics
, asked on 12/2/18
Difference between a transformer and a amplifier explain in detail
Answer
1
Raka Choudhury
Subject: Physics
, asked on 12/2/18
How the input and output signals in cimmon emmiter transistor amplifier are in opppsite direction?
Answer
1
Ayushi Aggarwal
Subject: Physics
, asked on 7/2/18
Explain
Answer
1
Deeksha Tanwar
Subject: Physics
, asked on 3/2/18
in transistor as amplifier , why we use capacitor in blockage of dc current by given ac source , even then battery is connected with transistor?
Answer
1
Guna Shekar
Subject: Physics
, asked on 30/1/18
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Answer
1
Souptik
Subject: Physics
, asked on 28/1/18
what is the meaning of resonating current?
Answer
1
Sakshi Sudhir Kudalkar
Subject: Physics
, asked on 27/1/18
what are the breakdown voltage of silicon pn junction and Ge pn junction....answer fast
Answer
1
Ashlesha
Subject: Physics
, asked on 27/1/18
Suppose a pure Si crystal has 5 × 10
28
atoms m
–3
. It is doped by 1 ppm concentration of pentavalent As. Calculate the number of electrons and holes. Given that
n
i
= 1.5 × 10
16
m
–3.
Answer
1
Sakshi Sudhir Kudalkar
Subject: Physics
, asked on 26/1/18
how does an LDR work in dark?...... answer fast!!
Answer
1
Yamini Jayachandran
Subject: Physics
, asked on 21/1/18
What would happen if light of other frequencies (other than sunlight) gets incident on a solar cell? Will it still work?
Answer
1
Chaitanya Kapoor
Subject: Physics
, asked on 11/1/18
Please solve this question
Q 26
Draw the circuit diagram to study the characteristics of npn transistor in common emiiter configuration.
Sketch typical i) input characteristics ii) output characteristics for such configuration.
explain how the current gain of transistor is calculated from output characteristics.
OR
Input signal A and B are applied to the input terminal of the dotted box set up shown here.Let Y be
the final output signal from the box.
draw the wave form of signal labelled C
1
and C
2
within the box, giving (in brief) the reason for the getting these wave forms.Hence draw the wave form of the final output signal Y.Give reason for your choice.What can we state ( in words) as the related between final output signal Y and the input signal A and B?
Answer
1
Prerna Varshney
Subject: Physics
, asked on 10/1/18
(i) Input resistance and (ii) Current amplification factor. How are
these determined using typical input and output characteristics ?
Answer
1
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What are you looking for?
Q.37. In only one of the circuits given in Fig. 14.40, the lamp L lights . Which circuit is it ? Give reason for your answer. [Delhi 2001 C]
13. Two metallic plates of equal length and thermal conductivity k1 and k2 are put together as shown in fig. The cross-sectional area of each rod is A. Find the equivalent thermal conductivity of composite rod. Ans : (k1 + k2)/2
Q 26
Draw the circuit diagram to study the characteristics of npn transistor in common emiiter configuration.
Sketch typical i) input characteristics ii) output characteristics for such configuration.
explain how the current gain of transistor is calculated from output characteristics.
OR
Input signal A and B are applied to the input terminal of the dotted box set up shown here.Let Y be
the final output signal from the box.
draw the wave form of signal labelled C1 and C2 within the box, giving (in brief) the reason for the getting these wave forms.Hence draw the wave form of the final output signal Y.Give reason for your choice.What can we state ( in words) as the related between final output signal Y and the input signal A and B?
these determined using typical input and output characteristics ?