When will a bulb be brighter? When the filament has a lower or higher resistance?

Question

When will a bulb be brighter? When the filament has a lower or higher resistance?

Answer 1

Higher resistance obviously dissipates more heat.

Electric rocket igniters use nichrome wire - a super high resistive material.  They glow bright red when a current passes through.

Conversely, superconductors have 0 resistivity and thus generate 0 heat.

Answer 2

with higher resistance of filament.  

Answer 3

It will be brighter if the filament has lower resistance.

Power P = V^2/R

V = voltage drop across the power source

R = resistance

P is more if R is less.

Note: Those who say that higher resistance will radidate more heat are going by the formula

H = i^2Rt

(H=heat, i=current,R=resistance,t=time)

It seems as if H is more if R is more. But in reality it is not so because i is not a constant. If R changes, then i also changes. Therefore, just because R increases, we should not jump to the conclusion that H will also increase.

In household applicances, if you put a bulb in a socket. If you remove that bulb and put another bulb of different resisance, then voltage remains the same.

So, we should use the formula

P = V^2/R

as I have done above.

Answer 4

The higher the resistance the more light it will radiate, but only if the element is driven to its maximum temperature. For example a low voltage into a high resistance will give little or no light, but a few volts into a low resistance, like a torch bulb, element will radiate a lot of light. To prove this just feed a variable voltage supply to a bulb and see for yourself. It is not only the resistance that determines the brightness.  

Answer 5

See MORE brightness = = = MORE POWER

P = V * I

Power(P) = Voltage(V) * Current(I)

V = 220 Volts (constant)

If Current is more Power is more.

R = Resistance = V / I

More I === Less R

THUS LESS RESISTANCE FILAMENT - BULB WILL BE BRIGHTER.  

Answer 6

In household electric supply, it is the voltage that is constant across the filament of the bulb. Power dissipated by the filament connected to a constant voltage supply, V is given by

Power = (voltage)^2 / resistance of the filament

=> lower the resistance more the power output and hence brighter the bulb.

Answer 7

The higher the resistance, the more electricity it converts to light, heat, sound or whatever.

So the one with more resistance.

Answer 8

The bulb with higher resistence will glow more b'coz it will be able to convert max. amount of electrical energy to light energy.