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Obtain the answers to (a) and (b) in Exercise 7.15 if the circ
Physics Part-I
Physics Part-I

Class 12

NCERT

Publisher:
NCERT
Subject:
Physics
1

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Chapter 3: Current Electricity

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Chapter 4: Moving Charges and Magnetism

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Chapter 5: Magnetism and Matter

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Chapter 6: Electromagnetic Induction

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7

Chapter 7: Alternating Current

37 questions

Q1
A 100 F capacitor in series with a 40 resistance is connected to a 110 V, 60 Hz supply.
(a) What is the maximum current in the circuit?

(b) What is the time lag between the current maximum and the voltage maximum?

Q2
Obtain the answers to (a) and (b) in Exercise 7.15 if the circuit is connected to a 110 V, 12 kHz supply? Hence, explain the statement that a capacitor is a conductor at very high frequencies. Compare this behaviour with that of a capacitor in a dc circuit after the steady state.
Q3
Keeping the source frequency equal to the resonating frequency of the series LCR circuit, if the three elements, L, C, and R are arranged in parallel, show that the total current in the parallel LCR circuit is imum at this frequency. Obtain the current RMS value in each branch of the circuit for the elements and source specified as below for this frequency.

The figure shows a series LCR circuit connected to a variable frequency source. , , .

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Chapter 8: Electromagnetic Waves

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Obtain the answers to (a) and (b) in Exercise 7.15 if the circuit is connected to a 110 V, 12 kHz supply? Hence, explain the statement that a capacitor is a conductor at very high frequencies. Compare this behaviour with that of a capacitor in a dc circuit after the steady state.

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Obtain the answers to (a) and (b) in Exercise 7.15 if the circuit is connected to a 110 V, 12 kHz supply? Hence, explain the statement that a capacitor is a conductor at very high frequencies. Compare this behaviour with that of a capacitor in a dc circuit after the steady state.
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(b)



Or ;
In absence of capacitor, current through the circuit
It follows that when frequency is very high current in the circuit is same, whether capacitor is connected in the circuit or not. In other words, at very high frequency, capacitor behaves like a conductor in an a.c. circuit. For d.c. supply,

Thus in d.c circuit, a capacitor amounts to an open circuit (offer infinite resistance).
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Q1
A 100 F capacitor in series with a 40 resistance is connected to a 110 V, 60 Hz supply.
(a) What is the maximum current in the circuit?

(b) What is the time lag between the current maximum and the voltage maximum?

Q2
Obtain the answers to (a) and (b) in Exercise 7.15 if the circuit is connected to a 110 V, 12 kHz supply? Hence, explain the statement that a capacitor is a conductor at very high frequencies. Compare this behaviour with that of a capacitor in a dc circuit after the steady state.
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Keeping the source frequency equal to the resonating frequency of the series LCR circuit, if the three elements, L, C, and R are arranged in parallel, show that the total current in the parallel LCR circuit is imum at this frequency. Obtain the current RMS value in each branch of the circuit for the elements and source specified as below for this frequency.

The figure shows a series LCR circuit connected to a variable frequency source. , , .

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Question Text
Obtain the answers to (a) and (b) in Exercise 7.15 if the circuit is connected to a 110 V, 12 kHz supply? Hence, explain the statement that a capacitor is a conductor at very high frequencies. Compare this behaviour with that of a capacitor in a dc circuit after the steady state.
TopicAlternating Current
SubjectPhysics
ClassClass 12
Answer TypeText solution:1
Upvotes26