Compute how far away the star can be away

Reference no: EM13306848

The threshold intensity for a human eye to sense the presence of light is 50 photons falling on the retina within a period of 0.1 s. Assume a star radiates with an output of 0.5x10^26 W in the visible spectrum, with a peak of wavelength=550 nm. (This star would be similar to the Sun, which radiates with 2.0x10^26 W). Estimate how far away the star can be away and still be visible to the unaided eye on a dark night. Assume the pupil of the observer's eye has a diameter of 1.0 cm. Give your answer in light years (do not insert a unit) Please show your work.

Reference no: EM13306848

Questions Cloud

Write recursive function that displays an arbitrary element : Your function should take a single integer argument that corresponds to the index of the element in the recursive sequence. The function should return the value of that particular element.

How strong was the magnetic field that produced this emf : Investigators are researching the appearance of a strange movement of objects in what the local community considers a haunted house. how strong was the magnetic field that produced this EMF

Solve for dv by dx and v using differential equations : Consider a simply supported beam with a uniformly distributed load q AND a concentrated load P at midspan. Solve for dv/dx and v using differential equations.

Write an output statement that displays the memory location : Write an output statement that displays the memory location of the value 4 stored in intArray[] in base-16 integer format.

Compute how far away the star can be away : The threshold intensity for a human eye to sense the presence of light is 50 photons falling on the retina within a period of 0.1 s. Estimate how far away the star can be away

Question about biochemical cycles and environmental change : Question about biochemical cycles and environmental change and do you think that environmental change is occurring naturally as part of a cycle or do you think that humans are negatively affecting the planet?

How much does the aggregate in the wheelbarrow weigh : You fill a 2 cubic foot wheelbarrow to the top with aggregate. If the specific gravity of the aggregate is 2.548 and 18% of the aggregate is void spaces, how much does the aggregate in the wheelbarrow weigh

What is the averaged induced current : A uniform magnetic field points out of the page. The field fully penetrates a wire loop in the plane of the page. what is the averaged induced current

Find the combined rate of discharge from the two orifices : A tank has two identical orifices, each 5 cm in diameter in one of its vertical sides and are situated one above the other. The upper orifice is 4 m below the water surfaceand the lower one is 6 m below the water surface.

User Account

All Pages