Answer:
The total applied force on the trolley is 5 N toward the North.
Explanation:
In this problem, Ben is pushing the trolley to north and Gary is pushing it to south. So both the forces are acting 180° opposite to each other. As force is a vector quantity, the net force or total force acting on any object should be calculated by vector addition of number of forces along with their directions. So in this case, if we consider the force Ben is applying as F1 and the force Gary is applying as F2 on the trolley. Then the net or total force acting on the trolley will be . This is because, F1 and F2 are acting opposite to each other in direction.Thus, .
So the total force acting on the trolley is 5 N and it is toward the north direction.
This is a question about the colligative property known as freezing point depression. Freezing point depression (the amount the normal freezing point of the solvent is decreased) can be calculated with this equation:
ΔT = i Kf<span> m
</span>
Where i (the van't Hoff factor) is the degree of dissociation of the solute, Kf is the freezing point depression constant, and m is the molality of the solution.
Here i = 2 (KCl dissociates into 2 ions, K+ and Cl-), Kf = 1.86 C/m (for water), and m = 0.743m).
ΔT = 2 x 1.86 C/m x 0.743m = <span>2.764C
</span>
That means the freezing point of the solution is 2.764C less than the pure solvent (water), making it 0C - 2.764C = -2.764C.
Answer:
Explanation:
A scientific investigation typically begins with observations. Observations often lead to questions. A hypothesis is a possible logical answer to a scientific question, based on scientific knowledge. A prediction is a statement that tells what will happen under certain conditions
Answer:
Hypothesis---experiments----results----conclusion.
Explanation:
First we make a hypothesis means a statement about why the tree looks unhealthy. In this segment of scientific method we have to test the hypothesis through experimentation. After that we have to take the readings of various parts of the tree and analyze the data to find out the problem. In the next step, we have to made the results on the basis of the data that is obtained. In the last we have to write the conclusion of the analysis and see the hypothesis.
<h3>
Answer:</h3>
Lead-205 (Pb-205)
<h3>
Explanation:</h3>
<u>We are given;</u>
We are supposed to identify its product after an alpha decay;
- Polonium-209 has a mass number of 209 and an atomic number of 84.
- When an element undergoes an alpha decay, the mass number decreases by 4 while the atomic number decreases by 2.
- Therefore, when Po-209 undergoes alpha decay it results to the formation of a product with a mass number of 205 and atomic number of 82.
- The product from this decay is Pb-205, because Pb-205 has a mass number of 205 and atomic number 82.
- The equation for the decay is;
²⁰⁹₈₄Po → ²⁰⁵₈₂Pb + ⁴₂He
- Note; An alpha particle is represented by a helium nucleus, ⁴₂He.