Answer:
Force
If you're taking classical physics, simply stated, a force is a push or a pull of some sort. But there is one other very important thing to understand about Force. A true Force is always an interaction (at least from a classical perspective). That means that forces always come in pairs. This is stated in Newton's Third Law (equal and opposite forces). Every action must have a reaction. This is required for all true forces. Another consequence of this is that force is a vector, meaning it has a magnitude and a direction. The action and reaction will always be opposite in direction.
A lot of people will say F=ma. This is true. However, it is important to keep in mind that this definition is a calculational tool. It is more precise to say the Sum of all forces=ma. The point is that ma is not a force. Forces are things like weight, tension, normal, friction, gravity, electrostatic, magnetic, and various other applied forces. The sum of forces on an object equals the product of its mass times its acceleration.
It is important to keep in mind that the force is on the object that accelerates. Another way to state this is that objects cannot accelerate themselves. You cannot push yourself back (or forwards). But if you push a heavy object like a desk forwards, then the desk can push you back.
Energy
There are many kinds of energy. There are two important things to know.
Energy is the ability to do work. It doesn't mean work is being done, but that work can be done. (So you can see there is an intimate relationship between work and energy).
Energy is conserved. That means the total amount of energy is always constant. If the energy is a system changes somehow, that means some work was done in order to move the energy from one system to another.
Energy is also a scalar (given that Work is a scalar).
<h2>
Answer: irregular</h2>
According to Hubble galaxies are classified into elliptical, spiral and irregular.
It should be noted this classification is based only on the visual appearance of the galaxy, and does not take into account other aspects, such as the rate of star formation or the activity of the galactic nucleus.
The classification is as follows:
1. Elliptical galaxies: Their main characteristic is that the concentration of stars decreases from the nucleus, which is small and very bright, towards its edges. In addition, they contain a large population of old stars, usually little gas and dust, and some newly formed stars.
2. Spiral galaxies: They have the shape of flattened disks containing some old stars and also a large population of young stars, enough gas and dust, and molecular clouds that are the birthplace of the stars.
3. Irregular Galaxies: Galaxies that do not have well-defined structure and symmetry.
In this context, galaxy M82 does not match with the first two types of galaxies, because it has not a defined shape.
Therefore, M82 is an irregular galaxy.
The momentum of an object is equivalent to the product of the object's mass and velocity. Computing the momentum for each ball:
A- 15 * 0.7 = 10.5
B- 5.5 * 1.2 = 6.6
C- 5.0 * 2.5 = 12.5
D- 1.5 * 5.0 = 7.5
Therefore, ball C has the greatest momentum.
The Photosphere is the right answer
Those are all "acceleration", caused by
unbalanced forces acting on the object.