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Why does the intensity decrease with the square of the distance from a point source?
Wiki User
∙ 9y ago
Intensity is defined as energy per unit area. As we move away from the point source, the area over which the energy distributes is generally spherical or hemispherical. The area of a sphere or hemisphere increases proportional to the square of radius, where the radius in this case is the distance from the point source. Thus Intensity, which is inversely proportional to area, decreases with the square of distance.
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Wiki User
∙ 9y ago
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How is the intensity of a sound related to the distance between the source and the receiver?
The intensity of a sound will decrease according to an inverse square law.
How does light intensity vary with distance form the source?
Light intensity is inversely proportional to the square of the distance: I = k/d2
What happens to the intensity of ionizing radiation when you move away?
The intensity reduces in proportion to the square of your distance from the source.
Does sound Intensity decrease linearly with distance?
No, it follows the inverse square law. That is, the intensity is inversely proportional to the square of the distance. I2/I1 = (r1/r2)². Intensity decreases with 1/r² from increased distance, while the sound pressure decreases only with 1/r from increased distance.
What is the relationship between the intensity of the radiation given off from a radiation source and distance from the radiation source?
The source doesn't care how far you are from it, or whether you're even there, andthere's no relationship between that and the intensity of the radiation it gives off.However, the intensity of the radiation that you receivefrom it is inversely proportionalto the square of your distance from it ... same math as for gravity.
How does distance affect intensity of radiation?
The source doesn't care how far you are from it, or whether you're even there, andthere's no relationship between that and the intensity of the radiation it gives off.However, the intensity of the radiation that you receivefrom it is inversely proportionalto the square of your distance from it ... same math as for gravity.
How does intensity vary with distance from the source?
It's an inverse-square law - for instance, double the distance, and the intensity will be reduced by a factor 1/4.This assumes that there is nothing absorbing the light (for instance, fog); if there is, the intensity in the above example will of course be even less than 1/4 the original intensity.
What distance increase is needed to reduce a sound's intensity from an initial 100dB to a final 80dB?
Sound intensity is inversely proportional to the square of the distancefrom the source.-- Increase the distance from the source by 10 times.-- Sound intensity decreases to 1/102 = 1/100 .-- 10 log ( 1/100 ) = -20 dB-- 100 dB - 20 dB = 80 dB
What is the purpose of the square root?
The purpose of a square root is to enable some calculations, For example,if you have a square with sides of 1 unit, then its diagonal has length sqrt(2) units,the power output of a sound wave is related to the square root of its amplitudethe intensity of light (or magnetic force, gravity) is inversely proportional to the square of the distance from the source so you would have to change the distance by *sqrt(x) to reduce the intensity to 1/x (increase the distance to sqrt(3) times as much to reduce the intensity to 1/3.
What happens to the intensity of light the further it is away from the source?
Light intensity is like gravitation. It changes in accordance with the inverse square law. What's an inverse square? if our number is.......................................... 5 ORIGINAL NUMBER the inverse of this number is.................... 1/5 INVERSE and the inverse SQUARE of this number is 1/52 or 1/25. INVERSE SQUARE But how does this answer your question? As a light source increases its distance from an object (moves farther away) its intensity changes, it becomes less intense. How much less intense? Think of the inverse square law! If your light source moves twice as far away (distance increases by a factor of 2) it becomes 1/4th as intense. (1/4th is the inverse square of 2) Think of shining a flashlight on a tile floor. If you are 5 cm (very close) to the floor, the light from the flashlight will cover one tile and be very intense. However, if you move twice (2 times) as far away, (now you would be 10cm from the floor) you would notice that the same light streaming from the flashlight can now cover four whole tiles! Two times the distance away now covers four whole tiles! Each tile is therefore receiving 1/4th the intensity of the light. Taking it one step further, if you were to move 4 times away (now you are 20cm from the floor)...the light from your flashlight could cover 16 tiles! So, each tile would be recieveing 1/16th the intensity of light. Like I said in the beginning, the same is true when you are working with the Universal Law of Gravitation, so, if you understand light intensity, you will also understand gravitation!
Does the intensity of a wave increases when its amplitude decrease?
Intensity of a wave is proportional to the square of its amlitude so it should decrese when the amplitude is decreased.
What is the maximum distance at which the riveter is still audible?
The intensity of a sound produced by a point source decreases as the square of the distance from the source. Consider a riveter as a point source of sound and assume that the intensities listed in Table 12.1 are measured at a distance 1 m away from the source. What is the maximum distance at which the riveter is still audible? (Neglect losses due to energy absorption in the air.)
