Question

In: Physics

How quickly does the flux of light from an isotropic source if, decrease with distance r?...

How quickly does the flux of light from an isotropic source if, decrease with distance r? For a perfectly collimated source, the flux does not decrease as one moves away from the source (as long as one stays within the beam). You have at your disposal two sources: an isotropic source and a collimated source. At a distance of 1 cm from the source, the flux from the isotropic source is one hundred times brighter. Which source is brighter fifty centimeters away? At what distance from the source arc the two equally bright?

Solutions

Expert Solution

Light flux or Brightness can be calculated by using intensity formula.

The solution is following in pictures....


Related Solutions

Consider the electromagnetic field produced at a given distance from a light source. Which of the...
Consider the electromagnetic field produced at a given distance from a light source. Which of the following statements are true? Check all that apply.  1. The intensity of the wave is inversely proportional to the square of the fields. 2. The intensity of the wave is proportional to the square of the fields. 3. The intensity of the wave is proportional to the speed of light. 4. The intensity of the wave is inversely proportional to the speed of light.
How much does the intensity level change if you increase your distance from the source by...
How much does the intensity level change if you increase your distance from the source by a factor of: (a) 2 (b)10 (c) 100?
The sound intensity is 0.0072 W/m2 at a distance of 20 m from an isotropic point...
The sound intensity is 0.0072 W/m2 at a distance of 20 m from an isotropic point source of sound. (a) What is the power of the source? (b) What is the sound intensity 6.1 m from the source? (c) What is the sound level 20 m from the source?
Does the eccentricity of the orbit increase or decrease as you shorten the initial distance of...
Does the eccentricity of the orbit increase or decrease as you shorten the initial distance of the planet from the star? Why would this be the case? (Based on my data the eccentricity of orbit decreased with shorter initial distances between the planet and star. Please explain why that is. Data is shown below) Trial Initial distance (thousand miles) d (thousand miles) c (thousand miles) T (days) Ti2/T02 di2/d02 eccentricity 0 91500 186000 185950 365 0.02 1 75000 128045 126422...
Light from a strongly unpolarized light source is reflected at the Brewster angle towards a water...
Light from a strongly unpolarized light source is reflected at the Brewster angle towards a water surface. The reflected light is directed towards a polaroid filter and after the filter the irradiance is measured. When the filter's transmission axis is parallel to the E-field result vector, a maximum irradiance of 500 W / m² is measured. a) What happens to the light in the Brewester angle? (Maximum half A4 page as explanation) b) If the filter is turned 25 °...
1. A _________________ _________ causes light rays from a distant source to converge to a _____________...
1. A _________________ _________ causes light rays from a distant source to converge to a _____________ ______________ 2. Charging by induction, a charged rod is brought near a neutral conductor: the electrons in the conductor redistribute such that there is a net positive charge away from the rod (T/F) 3. Electrical resistivity doesn’t change when temperature changes (T/F) 4. With a magnetic core, the total magnetic field is increased by a factor of 10^3 to 10^4 relative to the field...
Explain the concepts of “luminosity distance” and “proper distance”, and how they are different. How does...
Explain the concepts of “luminosity distance” and “proper distance”, and how they are different. How does the observed bolometric flux, f, from a distant source with luminosity, L, depend on redshift, z? What factor(s) cause(s) this redshift dependence? Describe the properties of a universe where the luminosity distance would be identical to the proper distance.
Is commercial laser a polarized source. How do you confirm that if any light source given...
Is commercial laser a polarized source. How do you confirm that if any light source given to you is polarized or not?
Two light bulbs are 1.00 mapart. From what distance can these light bulbs be marginally resolved...
Two light bulbs are 1.00 mapart. From what distance can these light bulbs be marginally resolved by a small telescope with a 3.90 cm-diameter objective lens? Assume that the lens is diffraction limited and λ=600nm.
a) How does the magnetic flux through the loop changes as the magnet rotates. Is the...
a) How does the magnetic flux through the loop changes as the magnet rotates. Is the flux maximal when the magnet is horizontal or vertical on the screen? Why? b) How does changing the magnetic flux works to create an emf (potential difference) in the coil, which alternates over time (use the Faraday’s law equation)?
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT