Complete Question:
Find the resistance of a wire of length 0.65 m, radius 0.25 mm and resistivity 3 * 10^{-6} ohm-metre.
Answer:
Resistance = 9.95 Ohms
Explanation:
<u>Given the following data;</u>
Length = 0.65 m
Radius = 0.25 mm to meters = 0.00025 m
Resistivity = 3 * 10^{-6} ohm-metre.
To find the resistance of the wire;
Mathematically, resistance is given by the formula;
Where;
- P is the resistivity of the material.
- L is the length of the material.
- A is the cross-sectional area of the material.
First of all, we would find the cross-sectional area of the wire.
Area of circle = πr²
Substituting into the equation, we have;
Area = 3.142 * (0.00025)²
Area = 3.142 * 6.25 * 10^{-8}
Area = 1.96 * 10^{-7} m²
Now, to find the resistance of the wire;
<em>Resistance = 9.95 Ohms </em>
16.1=4.472222 i hope this helps!!
Answer: In young's double slit experiment that uses monochromatic light the interference pattern formed has Central bright band with alternate dark and bright band That is option B.
Explanation: In this young experiment two small slits Namely a and b are formed on the screen and a monochromatic light is focused on them. Wavelets come out of of this lets scintillating and overlapping each other. This we get from huyginns principal, thus forming alternate dark and bright bands with bright band at center and all bands are about one meter apart.
Answer:
A: Dark matter is called “dark” because it doesn’t give off or interact with light — including through scattering. It is simply the nature of dark matter and why it is so difficult to study. But some models of dark matter state that on rare occasions, dark matter particles could be capable of interacting with normal matter, including by scattering light.
Astronomers know that dark matter is largely situated in spherical halos that enclose galaxies (more on that in a moment). If the dark matter in that halo scatters the galaxy’s starlight, even rarely, it could create a dim glow, like the halo of a light seen in thick fog. Researchers have searched for that glow but so far have not seen it. One possibility is that the glow is difficult to see at optical wavelengths, which is where past studies have focused. Scientists think such a glow, if it exists, might be easier to detect at longer infrared wavelengths, but no studies with the sensitivity needed to see this faint scattered light have been performed yet.
However, dark matter does have mass and its gravity can influence matter and light. So, dark matter does contribute to a phenomenon called gravitational lensing, in which a galaxy’s mass — including both its normal and dark matter — causes the space-time around it to curve. As light from an object in the background, such as a more distant galaxy, encounters this curved space-time, it appears to bend, which distorts and can even multiply the image of the background object. Astronomers do observe this effect, and by comparing the amount of gravity necessary to do the bending with the amount of visible matter, they have used it to confirm that galaxies are enshrouded in massive halos of dark matter.
Explanation:
TODO IS HERE BUT THAT QUESTION IS SH_T
