Ask a Doubt
Request a call back

Join NOW to get access to exclusive study material for best results

CBSE Class 12-science Answered

A coil is needed to operate an arc lamp of 150 V, 50 Hz. The lamp of resistance of 5 ohms when running at 10A. Find inductance of the choke coil, if the same arc lamp is to be operated on 160 V, DC. What is the additional resistance required? Compare the power losses in each case.
Asked by lekhakarthikeyan | 29 Jul, 2018, 04:16: PM
answered-by-expert Expert Answer
current in LR circuit begin mathsize 12px style equals space V over z space equals space fraction numerator V over denominator square root of R squared plus left parenthesis omega L right parenthesis squared end root end fraction space equals space fraction numerator 150 over denominator square root of 25 plus 4 pi squared cross times 50 cross times 50 cross times L squared end root end fraction space equals space 10 end style A ................(1)

V - voltage, z is impedence, R is resistance, ω(=2πf) is angular frequency anfd f = 50 Hz. L is inductance
 
Solving eqn.(1) for L , we get L = 0.045 Henry
 
when voltage is 160V, we calculate the resistance with the same formula by substituting L = 0.045 Henry.
In that case we get R = 7.5Ω. since the lamp resistance is 5Ω, we need to add 2.5Ω addiitinal resistance in the circuit
Answered by Thiyagarajan K | 31 Jul, 2018, 11:52: AM

Concept Videos

Multiple Choice Questions Practice Test
Answered Unanswered My Questions My Answers
CBSE 12-science - Physics
explain this concept
question image
Asked by panneer1766 | 24 Apr, 2024, 01:52: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 12-science - Physics
A dumbbell consists of two masses A and B each of mass m joined by a light rod of length l with mass B attached to a suspension point O by a light rod of length l as shown in figure. Find the minimum required speed with which mass A to be projected horizontally so that the system completes the vertical circular motion.
question image
Asked by artabandhusahu85 | 24 Apr, 2024, 12:07: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 12-science - Physics
What is charge?
Asked by niharvijayvargiya5 | 23 Apr, 2024, 06:40: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 12-science - Physics
please resolve with good explanation
question image
Asked by kulhariabhijeet | 21 Apr, 2024, 02:39: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 12-science - Physics
what are ghost particles please answer how is that not able to interact with other subatomic particles ..?is that faster than photons?
Asked by mohapatraswetalina88 | 21 Apr, 2024, 12:18: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 12-science - Physics
if breakdown voltage of each capacitor is 40v ,then maximum applied voltage Vmax will be
Asked by aishaisha091098 | 19 Apr, 2024, 04:54: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 12-science - Physics
explain
question image
Asked by ranadeb8090 | 19 Apr, 2024, 03:32: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 12-science - Physics
solve option e
question image
Asked by dasrituparna1999 | 13 Apr, 2024, 06:56: AM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 12-science - Physics
The number of moles in an elemental sample is just the ratio of the mass m to atomic mass 4. n= A The number of protons N, in an elemental sample is Z (atomic number) times the number of moles of Avogadro's number NA N=ZnN P A Copper has an atomic mass of 63.5 g/mole and 29 protons per atom. If such an atom were neutral, then it would have as many protons as electrons. If you remove electrons from a neutral state, then you get a net positive charge. Given a 54 gram ball of copper with a net charge of 2.2 µC, what fraction of the copper's electrons have been removed?
Asked by dasrituparna1999 | 12 Apr, 2024, 09:26: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 12-science - Physics
which answer is correct and most appropriate with explanation
question image
Asked by mishrigupta19319 | 08 Apr, 2024, 06:28: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
My Class Videos Tests ₹ Plans Ask a Doubt
Get Latest Study Material for Academic year 24-25 Click here
×