Scientists use models to help explain an idea, visualize hypotheses, and closely examine something (such as an atom).
Answer:
The concentration of mole evil at oxygen on that day is 0.00858 mol/L
Explanation:
Here, we want to calculate the concentration of molecular oxygen
The pressure on that day is 1.0 atm
Since oxygen is at a concentration of 21%, the pressure of oxygen will be 21/100 * 1 = 0.21 atm
Now let’s calculate the concentration;
From Ideal gas law;
PV = nRT
This can be written as;
P/RT = n/V
The term n/V refers to concentration;
Let’s make substitutions now;
P = pressure = 0.21 atm
R = molar gas constant = 0.0821 L•atm/mol•k
T = temperature = 25 = 25 + 273.15 = 298.15 K
Substituting these values, we have;
n/V = C = 0.21/(0.0821 * 298.15) = 0.00858 mol/L
For the work, applicate formula:
According our data:
W = 12000 N * 1,5 m
W = 18000 J
The work done is <u>18000 Joules.</u>
Answer:
the second one
Explanation:
When a free positive charge q is accelerated by an electric field, such as shown in Figure 1, it is given kinetic energy. The process is analogous to an object being accelerated by a gravitational field. It is as if the charge is going down an electrical hill where its electric potential energy is converted to kinetic energy. Let us explore the work done on a charge q by the electric field in this process, so that we may develop a definition of electric potential energy.
The electrostatic or Coulomb force is conservative, which means that the work done on q is independent of the path taken. This is exactly analogous to the gravitational force in the absence of dissipative forces such as friction. When a force is conservative, it is possible to define a potential energy associated with the force, and it is usually easier to deal with the potential energy (because it depends only on position) than to calculate the work directly.
