Answer:
The precise point is that gravitational energy is potential energy unless it makes something move, and then the energy is converted to kinetic energy, no work can be done. So a big rock at the top of a hill has no kinetic energy. Its only when it rolls down that work is done, and this can be converted to useful energy.
Explanation:
Glass and water are thicker and heavier than air. They are said to be 'denser' than air. What happens is that light slows down when it passes from the less dense air into the denser glass or water. This slowing down of the ray of light also causes the ray of light to change direction.
Democritus was the one who did not have experimental evidence to support his theory of the atom.
Answer: Option 4
<u>Explanation:
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The discovery of atoms were first stated by Democritus but due to the absence of any experimental proof, his statement was not noted as significant at that time.
After this, Dalton made the specific assumptions formulating some postulates for the atomic theory with proof. Then the cathode rays tube experiments performed by Thomson lead to the formation of plum pudding models of atom.
This is followed by Rutherford’s gold foil experiment discovering the presence of nucleus inside the atoms. So, Democritus first stated but due to absence of experimental evidences, his theory of atoms were not supported at that time.
The kinetic energy of an object is given by:
KE = 0.5mv²
KE = kinetic energy, m = mass, v = speed
Given values:
KE = 0.161J, v = 2.33m/s
Plug in and solve for m:
0.161 = 0.5m(2.33)²
m = 0.059kg
