Answer:
U = 1 / r²
Explanation:
In this exercise they do not ask for potential energy giving the expression of force, since these two quantities are related
F = - dU / dr
this derivative is a gradient, that is, a directional derivative, so we must have
dU = - F. dr
the esxresion for strength is
F = B / r³
let's replace
∫ dU = - ∫ B / r³ dr
in this case the force and the displacement are parallel, therefore the scalar product is reduced to the algebraic product
let's evaluate the integrals
U - Uo = -B (- / 2r² + 1 / 2r₀²)
To complete the calculation we must fix the energy at a point, in general the most common choice is to make the potential energy zero (Uo = 0) for when the distance is infinite (r = ∞)
U = B / 2r²
we substitute the value of B = 2
U = 1 / r²
ANSWER
C.
. newtons
EXPLANATION
According to Newton's second law,
, where
is the mass measured in kilograms.
and
is the acceleration in metres per second square.
We substitute these values to obtain,
.
We rearrange to get,
.
We multiply out the first two numbers and leave our answer in standard form to get,
.
The correct answer is C
At the end of the laps, the runner's displacement is zero.
Answer:
More reactant forms.
Explanation:
Given reaction is,
⇒
per mole
This is an Exothermic Reaction,(ΔE=-57.3KJper mole)
We know the equilibrium point of all Exothermic reactions moves leftward and more reactant is formed at the equilibrium.
<u>Reason:</u>
As heat is being produced in the reaction the additional heat(57.3KJpermole) can be <u>thought of as a product</u> of the reaction.
So,if you increase the temperature ,you provide heat energy,
(in other words heat energy is given) and hence the concentration of the products increases.
So, with respect to LeChateliers Principle,
As the concentration of products is increased by external means,more of the reactants are produced at the equilibrium of the reaction.
Therefore amount of reactants increases as <u>more reactant forms.</u>
Iron III ion is an iron ion with a +3 charge. If iron bonded with oxygen, it would form Fe2O3 which is rust. In this case, the oxidation number on Fe is +3 and it is -2 on oxygen. This would be called iron (III) oxide.
<span>The oxidation number of an ion times the number of the ions must equal zero when added together in a molecule with no charge. In this case, there are 2 iron molecules and each has a positive 3 charge. 2x3=6. There are three oxygen molecules each with a negative 2 charge. 3x-2=-6. 6+-6=0</span>