Inductors in Circuits
Trending Questions
Q. electric current flowing in the coil of self inductance 2mh is increased fro 1A to 2 A IN 2 ms.induced emf in the coil is
Q. Efficiency of a DC motor formula
Q. The network shown in the figure is part of a complete circuit. If at a certain instant, the current I is 5A and it is decreasing at a rate of 103 As–1 then VB–VA equals
![](https://df0b18phdhzpx.cloudfront.net/ckeditor_assets/pictures/823906/original_22q.png)
![](https://df0b18phdhzpx.cloudfront.net/ckeditor_assets/pictures/823906/original_22q.png)
- 20 V
- 15 V
- 10 V
- 5 V
Q. An inductor L, a resistance R and two identical bulbs B1 and B2 are connected to a battery through a switch S as shown in the figure. The resistance of coil having inductance L is also R. Which of the following statement gives the correct description of the happenings, when the switch S is closed ?
![](https://df0b18phdhzpx.cloudfront.net/ckeditor_assets/pictures/918561/original_Q18.png)
![](https://df0b18phdhzpx.cloudfront.net/ckeditor_assets/pictures/918561/original_Q18.png)
- The bulb B2 lights up earlier than B1 and finally both the bulbs shine equally bright.
- B1 light up earlier and finally both the bulbs acquire equal brightness.
- B2 lights up earlier and finally B1 shines brighter than B2.
- B1 and B2 light up together with equal brightness all the time.
Q. Three rods of same length and area of cross-section but of thermal conductivities K, 2K and 3K are connected in series in the same order. Free end of the first rod is at 0∘ C and free end of third rod is at 55∘ C. In steady state, temperature difference across the middle rod is
- 10∘ C
- 15∘ C
- 25∘ C
- 30∘ C
Q. The network shown in the figure is part of a circuit. If at a certain instant, the current I is 5 A flowing through the circuit part and it is decreasing at a rate of 103 As−1 then VB−VA equals
![](https://df0b18phdhzpx.cloudfront.net/ckeditor_assets/pictures/918495/original_Q16.png)
![](https://df0b18phdhzpx.cloudfront.net/ckeditor_assets/pictures/918495/original_Q16.png)
- 20 V
- 15 V
- 10 V
- 5 V
Q. Initially there is no current in the circuit, at t=0 sec. The growth rate of current at t=0 is r. After a long time when current becomes constant and is equal to i.
![](https://s3-us-west-2.amazonaws.com/infinitestudent-images/ckeditor_assets/pictures/445909/original_38.png)
![](https://s3-us-west-2.amazonaws.com/infinitestudent-images/ckeditor_assets/pictures/445909/original_38.png)
- r=0 and i=εR
- r=εL and i=εR
- r=εL and i=0
- r=Lε and i=εR
Q. A current of 2A is passed through a coil of 1000 turns, to produce a flux of 0.5 weber. What is the self inductance of the coil?
- 100 H
- 250 H
- 300 H
- 50 H
Q.
When a battery is connected across a series combination of self inductance L and resistance R, the variation in the current i with time t is best represented by
Q. An e.m.f. of 15 volt is applied in a circuit containing 5 henry inductance and 10 ohm resistance. The ratio of the currents at time t=∞ and at t =1 second is
- e12e12−1
- e2e2−1
- 1−e−1
- e−1
Q. Three rods of same length and area of cross-section but of thermal conductivities K, 2K and 3K are connected in series in the same order. Free end of the first rod is at 0∘ C and free end of third rod is at 55∘ C. In steady state, temperature difference across the middle rod is
- 10∘ C
- 15∘ C
- 30∘ C
- 25∘ C
Q. In series with 20 ohm resistor a 5 henry inductor is placed. To the combination an e.m.f. of 5 volt is applied. What will be the rate of increase of current at t = 0.25 sec
- e
- e−2
- e−1
- None of these
Q. When the current in the portion of the circuit shown in the figure is 2 A and increasing at the rate of 1 A/s, the measured potential difference Vab=8 V. However when the current is 2 A and decreasing at the rate of 1 A/s, the measured potential difference Vab=4 V. The value of R and L are
![](https://df0b18phdhzpx.cloudfront.net/ckeditor_assets/pictures/934170/original_Q7.png)
![](https://df0b18phdhzpx.cloudfront.net/ckeditor_assets/pictures/934170/original_Q7.png)
- 3 Ω and 2 H respectively
- 2 Ω and 3 H respectively
- 10 Ω and 6 H respectively
- 6 Ω and 1 H respectively.
Q. as current induces magnetic field and magnetic field induces current so will there be multiple inductions when a current carrying conductor is brought near a conducting loop?
Q. A potential difference of 6V is applied to a coil inductance 0.5H and a resistance of 4 ohm connected in series. The time taken for the current to reach half the maximum value is (in seconds)
- loge28
- loge24
- loge48
- loge44
Q. A coil of inductance 8.4 mH and resistance 6Ω is connected to a 12 V battery. The current in the coil is 1.0 A at approximately the time
- 500 sec
- 20 sec
- 35 milli sec
- 1 milli sec