Hypotheisis is just like an initial building block for a building. The true statements about hypothesis among the given are-
- First guess- hypothesis is a proposed explanation for something which is observed. Thus the explanation is just a guess and not a proved one.
- An initial idea which is assumed to be true - The whole experiment or research is based on an assumption which is supposed to be true and the scientist works to prove that true.
B)a force pushed the rock layers after they were formed
Explanation:
Reaction equation showing alpha decay in Uranium-238 is as follows.
It is known that an alpha particle is basically a helium nucleus and it contains 2 protons and 2 neutrons.
Symbol of an alpha particle is 
.
As atomic mass or weight is the sum of total number of protons and neutrons present in an atom.
Hence, the atomic weight of the alpha particle is (2 + 2) = 4.
The formula for kinetic energy is KE=1/2(mv²). Since both mass and velocity are multiplied by each other, particle with a larger mass needs to be moving slower than a particle with less mass if both have the same kinetic energy. You can think of it as 2KE/m=v² or 2KE/v²=m, If you increase the mass the velocity needs to decrease to keep the same KE value.
I hope this helps. Let me know in the comments if anything is unclear.
