________________
40
Jainism : Through Science If either a source of light or a light receiving surface is in motion and they come nearer to each other, their velocity becomes negative then r = d - v.t, where d is an initial distance between the source of light and light receiving surface. And if they go far apart from each other then r = d+v.t
.: I = coc/4nt (d 1 v t)2
This formula can be used only for direct light but not for reflected and concentrated light. Doppler's effect can easily be known by this formula.
In this formula 'e' does not depend only upon the area of light emitting body but it also depends upon the specific resistance of metal., length of filament and area of a cross section of the filament and it can be determined from the following formula of electricity.
In electricity, intensity of light depends upon the watt of a bulb. e. g. Light intensity of 40 Watt bulb is more than 25 watt bulb, in the same way light intensity of 60 watt bulb is more than that of 40 watt bulb. In short as watt increases intensity increases.
But W=IR (Where W = watts. I = current in amp. and R=Resistance in ohms) and R = 3 l/a (Where R= Resistance, S = Specific Resistance of metal, l = length of filament in cms., a=area of a cross section of filament in square cms.)
Suppose in case of electric bulbs of same company a specific resistance of tungston metal and area of a cross section of the filament might be same forever then R, resistance is directly variable with length of filament. Therefore as length of filament increases resistance increases and with the increment in length of filament watt also-increases, if there will not be any change in current I. But, in practice, it is not possible.
Absolute temperature has not been considered here because, it affects only on the frequency of each photon.
