Answer: 0.24g/ml
Explanation:
Given that:
Volume of water displaced = 23.5 ml
Mass of cork = 5.7 g
Density of the cork = ?
Recall that density is obtained by dividing the mass of a substance by the volume of water displaced.
i.e Density = Mass/volume
Density = 5.7g /23.5ml
Density = 0.24g/ml
Thus, the density of the piece of cork is 0.24g/ml
Answer:
A) if each astronaut breathes about 500 cm³, the total volume of air breathed in a year is 14716.8m³.
B) The Diameter of this spherical space station should be 30.4m
Explanation:
The breathing frequency (according to Rochester encyclopedia) is about 12-16 breath per minute. if we take the mean value (14 breath per minute), we can estimate the total breaths of a person along a year:
If we multiply this for the number of people in the station and the volume each breath needs, we obtain the volume breathed in a year.
The volume of a sphere is:
So the diameter is:
![D=2r=2\sqrt[3]{\frac{3V_{sph}}{4\pi}} =30.4m](https://tex.z-dn.net/?f=D%3D2r%3D2%5Csqrt%5B3%5D%7B%5Cfrac%7B3V_%7Bsph%7D%7D%7B4%5Cpi%7D%7D%20%3D30.4m)
Answer: C, constant, you’re welcome
Explanation:
Suppose you want to shine a flashlight beam down a long, straight hallway. Just point the beam straight down the hallway -- light travels in straight lines, so it is no problem. What if the hallway has a bend in it? You could place a mirror at the bend to reflect the light beam around the corner. What if the hallway is very winding with multiple bends? You might line the walls with mirrors and angle the beam so that it bounces from side-to-side all along the hallway. This is exactly what happens in an optical fiber.
The light in a fiber-optic cable travels through the core (hallway) by constantly bouncing from the cladding (mirror-lined walls), a principle called total internal reflection. Because the cladding does not absorb any light from the core, the light wave can travel great distances.
However, some of the light signal degrades within the fiber, mostly due to impurities in the glass. The extent that the signal degrades depends on the purity of the glass and the wavelength of the transmitted light (for example, 850 nm = 60 to 75 percent/km; 1,300 nm = 50 to 60 percent/km; 1,550 nm is greater than 50 percent/km). Some premium optical fibers show much less signal degradation -- less than 10 percent/km at 1,550 nm.
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