Answer:
D Electromagnetic and gravitational
Answer:
atom -
the smallest particle of a chemical element that can exist.
atomic mass-
the quantity of matter contained in an atom of an element
atomic weight -
ratio of the average mass of a chemical element's atoms to some standard
protons-
stable subatomic particle that has a positive charge equal in magnitude to a unit of electron charge and a rest mass of 1.67262 × 10−27 kg
electrons-
a stable subatomic particle with a charge of negative electricity, found in all atoms and acting as the primary carrier of electricity in solids
neutrons-
a subatomic particle of about the same mass as a proton but without an electric charge, present in all atomic nuclei except those of ordinary hydrogen.
energy levels-
one of the stable states of constant energy that may be assumed by a physical system
[used especially of the quantum states of electrons in atoms and of nuclei. — called also energy state.]
Covalent bonds
the interatomic linkage that results from the sharing of an electron pair between two atoms.
ionic bonds
type of linkage formed from the electrostatic attraction between oppositely charged ions in a chemical compound.
Valence electrons
a single electron or one of two or more electrons in the outer shell of an atom that is responsible for the chemical properties of the atom.
Lewis Dot Diagram
A way of representing atoms or molecules by showing electrons as dots surrounding the element symbol. One bond is represented as two electrons.
"Gamma rays" is the name that we call the shortest of all electromagnetic waves. They're shorter than radio waves, microwaves, infrared waves, heat waves, visible light waves, ultraviolet waves, and X-rays. They extend all the way down to waves that are as short as the distance across an atom.
Being so short, they carry lots of energy. They can penetrate many materials, and they can damage living cells and DNA. They're dangerous.
The sun puts out a lot of gamma radiation. The atmosphere (air) filters out a lot of it, otherwise there couldn't even be any life on Earth.
As soon as astronauts fly out of the atmosphere, they need a lot of shielding from gamma rays.
You know the precautions we take when we're around X-rays. The same precautions apply around gamma rays, only a lot more so.
It's only in the past several years that we've learned how to MAKE gamma rays without blowing things up. Also, how to control them, and how to use them for medical and industrial applications.
Answer:
V = V0 + a t
V = 75 - 9.8 * 3 = 45.6 m/s
