QED calls for the upholding of the inverse square law with reference to light because photons have a vanishing pole mass. The prediction holds with other massless particles, and explains the inverse square law of gravitational force. Newton also dabbled with the Inverse Square Law in his study of gravity, where he measured the periods and diameters of the orbits of Jupiter and Saturn. He found that the forces on Jupiter and Saturn, exerted by the sun, were proportional to the inverse of the distance squared.
Although the inverse square law applies to sound, gravity, and electric fields, Bullialdus focused on light to test this theory. He did this by showing that the intensity of light I at a given distance from the origin of the light was the power output of the light source S was proportional to inverse of the squared distance.
This did not only explain that light decreases over a distance, common knowledge at the time, but that it decreases at a specific proportion to the inverse of the distance squared. This works because the Power output of the light source has to be divided by the surface area it has to cover.
The aim in this investigation is to determine whether the intensity of light decreases as a proportion of the inverse of the distance squared, and I hypothesise that the real-world results will reconcile with the math.
If I measure the intensity of light at a given distance of r, it will decrease proportionally to the inverse of the distance squared. Controls: ambient light in the room, wattage of bulb, increment of measurement, reflective surfaces in the room, reflective potential of my body, angle of lightbulb, height of lightbulb. I had to use multiple conversions and calculations to reconcile my data.
The sensor measured the luminous flux per square meter in Lux, which equals one lumen per square meter. The first tool is the most ubiquitous—the metal scrim. Increasing the light intensity photon energy per second per unit area increases the rate at which electrons leave the metal, and the electrons have more kinetic energy. Changing the frequency of the light while keeping the intensity constant should not change the rate of electron emission.
Yes, the intensity depends, in part, on the frequency. If the frequency of electromagnetic waves is higher than the extraction threshold of the metal and electrons are emitted from the metal surface, then an increase of light intensity will result in a proportional increase of electrical current of the electrical circuit where the emitted electrons are conveyed.
This current is the number of electrons being emitted per second. That is directly proportional to the intensity of the light. So greater intensity means more photons striking the surface and hence an increase in the emitted electrons. Measuring the intensity of a source is sampling the number of photons emitted from the source in some particular time period, which is directly related to the number of disintegrations in the same time period the activity. Intensity also called chroma or saturation is the brightness or dullness of a color.
A color as we see it on a color wheel is at full intensity bright. When we mix it with gray, black, or white, it becomes dull. Colors also lose intensity when mixed with their complement the opposite color on the wheel.
In particle nature, intensity is related to number of photons in the radiation. FITT stands for frequency, which is how often you exercise, intensity, which is how hard you exercise, time, which is how long each session lasts and what time of day you exercise, and type, which is what activities you do.
All of these pieces are interconnected and have to be considered as a whole. Lets start with the relationship between duration and exercise intensity: duration is the amount of time in which you participate in a single bout of exercise, and intensity is a measure of how hard you work during a single workout.
Suppose you were to use a light meter to measure an initial intensity I i , or brightness, a distance r from a light source.
Suppose that some time later the brightness of the light is either greater or lesser; if the intensity diminished you would know that the source was moving away from you and if it became brighter you would know that the source was moving towards you assuming the light source itself remained the same.
This relationship can be illustrated by the diagram below, which shows the apparent brightness of a source with luminosity L 0 at distances r, 2r, 3r, etc. Notice that as the distance increases, the light must spread out over a larger surface and the surface brightness decreases in accordance with a "one over r squared" relationship.
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