Mass is a measure of a body's inertia in which the SI unit is the kilogram.
Weight is the force that gravity exerts upon a body in direct proportion to its mass.
Energy is the capacity of a body to do work. Mass and energy are directly proportional according to Einstein's famous equation, E=mc^2.
In physics, mass is the aggregate of matter in a body that is a measure of its inertia.
Weight is defined as the force that an object of mass M experiences in a gravitational field. Where mass comes from and why it is the quantity which interacts via the gravitational force is a more fundamental and unanswered question in physics.
mass=density*volume
Force times distance
In physics, velocity is defined as the rate of change of position
It is important to learn many things in physics. Inertia Force is defined as a force opposite to an accelerating force acting on a body, and equal to the product of the accelerating force and the mass of the body.
Axiom
Physics is the basis for all other sciences. Chemistry is primarily ruled by protons and electrons. Their existence behavior and charges are defined by physics. Biology is just incredibly advanced chemistry that can perform basic Newtonian physics. Geology is thermal physics and plate tectonics(high mass low velocity collisions). Astronomy is gravity, collisions, and extreme temperature interactions (also quite a bit of chemistry, but that's just physics). You get the picture. Physics is a description of everything.
Yes
Yes, density is defined as mass divided by volume, and mass doesn't change when you take something on a spaceship.Yes, density is defined as mass divided by volume, and mass doesn't change when you take something on a spaceship.Yes, density is defined as mass divided by volume, and mass doesn't change when you take something on a spaceship.Yes, density is defined as mass divided by volume, and mass doesn't change when you take something on a spaceship.