The answer is false. The speed of the astronaut cancels out the force of gravity, causing a 'stationary freefall'. While under these effects, it is not required for an astronaut to 'strengthen' his body.
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.
1
Answer:
energy per unit charge
Explanation:
EMF is energy per unit charge and has unit joule/ coulomb, where joule is unit of energy and coulomb is the unit of charge.
Slicing a tomato is still considered a physical change because you are only altering the shape of it by slicing it. It does not change color or make bubble when slicing the tomato. Therefore, it is still a physical change
hope this helps:)
The trip from Camp Wood to the Pacific
Ocean and back again took 1.5 years to complete.<span>
</span>
<span>The </span>Lewis<span> and Clark </span>Expedition<span> from May 1804 to September 1806, also known as
the Corps of Discovery </span>Expedition, was the first
American expedition<span> to
cross what is now the western portion of the United States.</span>
