<span>The scientists discovered that when they organized elements in order of increasing atomic mass there is a pattern of repetition of properties (A). The periodic law was developed by Dmitri Mendeleev and Lothar Mayer in 1869. They worked independently of each other and both created a periodic table. They both arranged the items on the table by weight and both suggested that certain properties of the elements recur. The Mendeleev table is the most important table because the values for the atomic mass are the most accurate.</span>
Answer:
Newton's Cradle is a neat way to demonstrate the principle of the CONSERVATION OF MOMENTUM.
What happens here is when the ball on one end of the cradle is swung and it hits the other balls that are motionless, or stationary, the momentum of the swinging ball is transferred to the next ball upon impact.
Momentum is not lost in this action, what happens when it hits the next ball, the momentum is transferred to the next one, and then the next, and the the next, till it reaches the last ball on the other end. Since nothing is next to the last ball, it pushes the ball upwards, which will swing down and repeat the process going the other way.
This also demonstrates the CONSERVATION OF ENERGY. As you will see, the energy continues to move through the other balls, passing it from one ball to the other, which keeps this constantly moving.
I think the correct answer from the choices listed above is option D. Outer planets are mostly made up of gases and are huge in size. These gases are hydrogen and helium. <span>These outer planets are Saturn, Jupiter, Uranus, and Neptune. Hope this answers the question.</span>
