Electrical Engineering - Energy and Power - Discussion
Discussion Forum : Energy and Power - General Questions (Q.No. 1)
1.
A 33 
half-watt resistor and a 330 half-watt resistor are connected across a 12 V source. Which one(s) will overheat?
half-watt resistor and a 330 half-watt resistor are connected across a 12 V source. Which one(s) will overheat?33
330
both resistors
neither resistor
Discussion:
58 comments Page 3 of 6.
D Shwetha said:
7 years ago
Here, it is given that, the resistors are 0.5W & also a parallel connection.
Heat is directly proportional to power (H=P*t). So, power rating 0.5W & Heat is also both resistors are same.
Heat is directly proportional to power (H=P*t). So, power rating 0.5W & Heat is also both resistors are same.
J D D said:
7 years ago
The resistor will overheat because the capacity of both resistors are 5watt And due to 12v supply no one will take higher current than it's rated capacity. (respectively i1=0. 3636, i2=. 03636).
Sagar singh said:
1 decade ago
Since they are connected in parallel and 33 ohm is very less than 330 ohm more current will flow through 33 ohm, and therefore more heat will dissipate across 33 ohm and it gets over heated.
Suresh Maniar said:
1 decade ago
Both Resistances are Connected across same voltage of 12V.
Wattage=V square/R since V=Const or same for both smaller are value shall draw more power and heat up more.
Wattage=V square/R since V=Const or same for both smaller are value shall draw more power and heat up more.
Himanshu said:
1 decade ago
Option d is correct as both are taking same power and are connected in parallel (as given in question they are conected across 12 we supply. Across means parallel).
Ankit Bhardwaj said:
1 decade ago
No need to calculate anythin as it's
given in the que. that both the resistors are of same
ratings i.e 1/2 watts....
thats why heat dissipation shall be same...!
given in the que. that both the resistors are of same
ratings i.e 1/2 watts....
thats why heat dissipation shall be same...!
Akshay jadhav said:
7 years ago
Power of both are same so only current will be change. The output of the resistor in the form of heat that heat output is remains same for both for same wattage.
Munawar said:
1 decade ago
It is [A] 33 W will overheat, because its wattage VI = 12*12/33 = 4.36 W against the allowed 0.5 W. For 330 W, wattage = 12*12/330 = 0.436 W within the 0.5 W.
Shekhar said:
1 decade ago
When the resistance of the conductor is more then current drop will be more then heat will generat more as compare to low resistance of the conductor.
Dayo said:
1 decade ago
Both resistors are connected in series, therefore same voltage flow across each of them & there s also balance in heat dissipated by each.
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