Answer:
Solids
:A solid has a definite shape and volume because the molecules that make up the solid are packed closely together and move slowly. Solids are often crystalline; examples of crystalline solids include table salt, sugar, diamonds, and many other minerals. Solids are sometimes formed when liquids or gases are cooled; ice is an example of a cooled liquid which has become solid. Other examples of solids include wood, metal, and rock at room temperature. Liquids
: A liquid has a definite volume but takes the shape of its container. Examples of liquids include water and oil. Gases may liquefy when they cool, as is the case with water vapor. This occurs as the molecules in the gas slow down and lose energy. Solids may liquefy when they heat up; molten lava is an example of solid rock which has liquefied as a result of intense heat. Gases
: A gas has neither a definite volume nor a definite shape. Some gases can be seen and felt, while others are intangible for human beings. Examples of gases are air, oxygen, and helium. Earth's atmosphere is made up of gases including nitrogen, oxygen, and carbon dioxide. Plasma: Plasma has neither a definite volume nor a definite shape. Plasma often is seen in ionized gases, but it is distinct from a gas because it possesses unique properties. Free electrical charges (not bound to atoms or ions) cause the plasma to be electrically conductive. The plasma may be formed by heating and ionizing a gas. Examples of plasma include stars, lightning, fluorescent lights, and neon signs.
Explanation:
A ... No. Every element has an Atomic Number.
Helium's Atomic Number is 2.
It's Atomic Mass is 4.
B ... No. This isn't true for ANY element.
C ... Yes. This is true for EVERY element except Hydrogen.
D ... No. This is true for ONLY Hydrogen.
Cosmic, or background, radiation is the small amount of high energy radiation which is mostly left over from the big bang or from supernovas. It is mostly single protons, but also alpha particles and even sometimes heavier elements. It can also refer to the low levels of electromagnetic radiation present all over the universe.
The frequency of light from a laser is 4.878 x10^ 14 s-1 hertz
<h3>Steps</h3>
v= c/ lambda
c= 3.00 x10^8 m/s
nm into meters
615nm (1m/ 1x10^9 nm) = 6.15x 10^-7 m
use frequency formula
v = 3.00 x10^8 m/s // 6.15 x10 ^-7
v = 4.878 x10^ 14 s-1 hertz
The frequency of light from a laser is 4.878 x10^ 14 s-1 hertz
<h3>What do you mean by frequency?</h3>
- The quantity of waves that pass a set location in a predetermined period of time is known as frequency.
- Therefore, if a wave passes through in half a second, the frequency is 2 per second.
- The frequency is 100 times per hour if it takes 1/100 of an hour.
learn more about frequency here
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Answer: The displacement is 1 block.
Explanation:
Let's define:
The right is the positive side.
The left is the negative side.
Then if you start at position A, and you walk N blocks to the right, the new position is:
A + N
And if you start at position A, and you walk M blocks to the left, the new position is:
A - M.
In this case, we know that Kayla starts at -3 and she walks 5 blocks to the right.
Then her new position is:
-3 + 5 = 2
Now she walks 3 blocks to the left, then her new position is:
2 - 3 = -1
The displacement will be equal to the difference between the final position (-1) and the initial position (-2)
Then the displacement is:
D = -1 - (-2) = -1 +2 = 1
The displacement is 1 block.
