Answer:
The person has been dead for approximately 15,300 years
Explanation:
<u>Available data</u>:
- The half-life of carbon 14 is 5,600 years
- The human skeleton level of carbon 14 is 15% that of a living human
To answer this question we can make use of the following equation
Ln (C14T₁/C14 T₀) = - λ T₁
Where,
- C14 T₀ ⇒ Amount of carbon in a living body at time 0 = 100%
- C14T₁ ⇒ Amount of carbon in the dead body at time 1 = 15%
- λ ⇒ radioactive decay constant = (Ln2)/T₀,₅
- T₀,₅ ⇒ The half-life of carbon 14 = 5600 years
- T₀ = 0
- T₁ = ???
Let us first calculate the radioactive decay constant.
λ = (Ln2)/T₀,₅
λ = 0.693/5600
λ = 0.000123
Now, let us calculate the first term in the equation
Ln (C14T₁/C14 T₀) = Ln (15%/100%) = Ln 0.15 = - 1.89
Finally, let us replace the terms, clear the equation, and calculate the value of T₁.
Ln (C14T₁/C14 T₀) = - λ T₁
- 1.89 = - 0.000123 x T₁
T₁ = - 1.89 / - 0.000123
T₁ = 15,365 years
The person has been dead for approximately 15,300 years
Answer:
<em>The correct option is D) The energy of the car will decrease, and the energy of the block will increase. </em>
Explanation:
As we know energy cannot be created or destroyed but it can change from one form to another. When the wooden car will collide with the wooden block, some of the kinetic energy with which the car was moving will be passed to the wooden block. As a result, the wooden block will also get pushed along the track. Meanwhile, as the wooden car had transferred some of its energy, its energy level will decrease and it will move slower than before pushing the wooden block along with it.
Answer:
C) it is a polarized molecule, where the oxygen is slightly positive and the hydrogens are slightly negative.
Explanation:
The water molecule is polarized, but the oxygen atom is slightly negative and the hydrogens are slightly positive.
Electronegativity is a property that measures how much an atom will tend to attract electrons towards itself. Because electrons are negatively charged, the more electronegative an atom is, the more negative its partial charge will be.
Oxygen is much more electronegative than hydrogen, and thus it will attract the electrons in the molecule, keeping them away from the hydrogens.
B and C are the correct answers
Answer:
the conclusion
Explanation:
You could find the answer using the steps of scientific experiment
the steps are:
Get purpose.
build up a hypothesis.
Test the hypothesis and collect data.
Analyze the data.
Draw conclusion.
Communicate results with others
In this case we could see that a student is trying to determine if plant's growth are affected by the type of soil we use, by seeing the steps of the scientific method, we could say that this is the last step of the experiment. So, it is considered as the conclusion.
