I believe you're asking about Helium with two numbers to the left of it.
Once number is on top of the other.
The 4, which is on top, represents the atomic mass. Helium's atomic mass is 4.
The 2, which is on bottom, represents the number of protons (or atomic number). Helium's number of protons is 2.
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It refracts.
The change in the speed of light is called Refraction. This process occurs when light comes in contact with objects of different compositions and structures. Polarization occurs when light only propagates in a particular plane, as opposed to propagating in all.
Certain metals such as steel,aluminium follow sustainable methods but some does not.
Explanation:
Metal production means conversion of a raw material, such as a metallic ore, to a final form which can be used for some commercial or industrial purpose. In some cases, metal production gives few steps since the metal already occurs in an elemental form in nature.
Sustainable manufacturing is the creation of manufactured products through economic processes that minimize negative environmental impacts while conserving energy and natural resources.
Steel is a uniquely sustainable material because Steel is truly recyclable and is truly recycled.
Aluminum poses no danger of environmental toxicity therefore, secondary aluminum production from recycling scrap has the potential to significantly reduce greenhouse gas emissions.
But some metals production does not follow subsequent methods.
- Pressure = 2000 Pa
- Mass = 100 Kg
- We know, Force = mass × acceleration due to gravity
- Acceleration due to gravity = 9.8 m/s^2
- Therefore, the force = (100 × 9.8) N = 980 N
- We know, Pressure =
- Therefore, area of contact
<u>Answer:</u>
<u>0</u><u>.</u><u>4</u><u>9</u><u> </u><u>m/</u><u>s^</u><u>2</u>
Hope you could understand.
If you have any query, feel free to ask.
The speed of a beam of light will appear the same to all observers.
<h3>Speed of light:</h3>
The exact distance that light travels in a vacuum in a second is 299,792,458 meters (983,571,056 feet). This is roughly 186,282 miles per second, or "c," the symbol for light speed in mathematics.
According to Einstein's theory of special relativity, an object (such as a single photon of light) cannot appear to move faster than the speed of light. This physical rule is not broken by Nemiroff's experiment since the laser pointer emits a stream of photons rather than a single photon.
Nothing can move faster than light in a vacuum, according to one of physics' most revered rules. However, in a recent experiment, this speed restriction was broken when a laser pulse traveled at more than 300 times the speed of light.
Learn more about speed here:
brainly.com/question/13202563
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