Answer: Bohr's model (1913)
Niels Bohr improved Rutherford's model. Using mathematical ideas, he showed that electrons occupy shells or energy levels around the nucleus. The Dalton model has changed over time because of the discovery of subatomic particles.
Bohr's model (1913)
Niels Bohr improved Rutherford's model. Using mathematical ideas, he showed that electrons occupy shells or energy levels around the nucleus. The Dalton model has changed over time because of the discovery of subatomic particles
Dalton's atomic theory proposed that all matter was composed of atoms, indivisible and indestructible building blocks. While all atoms of an element were identical, different elements had atoms of differing size and mass.
John Dalton
The idea that everything is made of atoms was pioneered by John Dalton (1766-1844) in a book he published in 1808. He is sometimes called the "father" of atomic theory, but judging from this photo on the right "grandfather" might be a better term.
Explanation:
<u>Answer</u>
longitudinal wave because the particles move parallel to the direction that the wave is traveling.
<u>Explanation</u>
There are 2 types of a wave, electromagnetic and mechanical wave. These waves can also be categorized into two, longitudinal ans transverse waves.
longitudinal wave is a wave whose particles vibration is in the direction of wave travel.
Transverse wave is a wave whose vibration of particles is perpendicular to the direction of wave travel.
Answer:
The friction force is 250 N
Explanation:
The desk is moving at constant velocity. This means that its acceleration is zero: a = 0. Newton's second law states that the resultant of the forces acting on the desk is equal to the product between mass (m) and acceleration (a):

In this case, we know that the acceleration is zero: a = 0, so also the resultant of the forces must be zero:
(1)
We are only interested in the forces acting along the horizontal direction, since it is the direction of motion. There are two forces acting in this direction:
- the pull, forward, F = 250 N
- the friction force, backward, 
Given (1), we have

So the force of friction must be equal to the pull:

Answer it will move slower:
Explanation: cause the force that’s opposite of it
dollar bills if so def. not me but grades 4