Electrical Engineering - Series Circuits - Discussion
Discussion Forum : Series Circuits - General Questions (Q.No. 5)
5.
Which of the following series combinations dissipates the most power when connected across a 120 V source?
one 220 
resistor
resistortwo 220 resistors
resistorsthree 220 resistors
resistorsfour 220 resistors
resistorsDiscussion:
44 comments Page 3 of 5.
Rupesh said:
1 decade ago
What about maximum power transfer theorem? Which says the max power will be transferred to the load when load impedance is equal to the source impedance. It means if load independence is greater than the source impedance then the power transferred to the load is less and vice versa. If we match both the incidences we can get max power and max heat dissipation. So the question is what is the value of source impedance of 120 volt source?
Sriksnth said:
1 decade ago
P = v^2/r.
Power is inversely proportionally to resistance. So, as resistance is less power will be more.
Option A is correct.
Power is inversely proportionally to resistance. So, as resistance is less power will be more.
Option A is correct.
Ramesh said:
1 decade ago
Can any one explain? What happens if parallel combination is there?
Rajesh said:
1 decade ago
For a single resistor voltage drop is maximum across that resistor, so power is maximum. But when two or more resistor come into picture then voltage drop across the resistance will be lesser than previous one so power will be less.
Sanoop said:
1 decade ago
P = V^2/R.
If R decreases then Power increases.
P = I^2.R.
If R decreases then current increases since I^2 is considered for power calculation, increase in current will be considered over increase in resistance.
If R decreases then Power increases.
P = I^2.R.
If R decreases then current increases since I^2 is considered for power calculation, increase in current will be considered over increase in resistance.
Satyaranjan acharya said:
10 years ago
Very simple thing friends P = V*I.
In this case we can increase power by two process either by increasing current or by increasing voltage though power is directly proportional to the current & voltage.
But in this question voltage is constant so we have to consider the current for solve this question. And current is higher in one resistance in comparision to series combination of 4 resistance. So the answer is "A".
In this case we can increase power by two process either by increasing current or by increasing voltage though power is directly proportional to the current & voltage.
But in this question voltage is constant so we have to consider the current for solve this question. And current is higher in one resistance in comparision to series combination of 4 resistance. So the answer is "A".
Apiaps said:
10 years ago
v = IR = I = V/R as are reduces I increases.
And P = I^2 *R.
As R reduces I increases as p increases.
And P = I^2 *R.
As R reduces I increases as p increases.
SHAMIK said:
10 years ago
P = V^2/R.
As R increases, P decreases.
As R increases, P decreases.
RAMESH said:
9 years ago
Nice explination @Sadik Pasha.
Jayaram said:
9 years ago
Nice explanation, Thank you all.
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