Answer:
C : Steel
Explanation:
Steel is manufactured and not made by the Earth itself
Industrially biomass, living or recently experienced obtain fuel from biological material or by using other industrial purposes are related. Widely, with the goal of obtaining biofuels fibers with cultivated plants, heat and chemicals used to obtain the means of animal and vegetable products. Biomass, organic waste can be burned as a fuel composition. However, geographical impact modified with, coal, organic materials such as oil-free. Are usually measured by dry weight
Quasi frequency = 4√6
Quasi period = π√6/12
t ≈ 0.4045
<u>Explanation:</u>
Given:
Mass, m = 20g
τ = 400 dyn.s/cm
k = 3920
u(0) = 2
u'(0) = 0
General differential equation:
mu" + τu' + ku = 0
Replacing the variables with the known value:
20u" + 400u' + 3920u = 0
Divide each side by 20
u" + 20u' + 196u = 0
Determining the characteristic equation by replacing y" with r², y' with r and y with 1 in the differential equation.
r² + 20r + 196 = 0
Determining the roots:
r = -10 ± 4√6i
The general solution for two complex roots are:
y = c₁ eᵃt cosbt + c₂ eᵃt sinbt
with a the real part of the roots and b be the imaginary part of the roots.
Since, a = -10 and b = 4√6
u(t) = c₁e⁻¹⁰^t cos 4√6t + c₂e⁻¹⁰^t sin 4√6t
u(0) = 2
u'(0) = 0
(b)
Quasi frequency:
μ =
(c)
Quasi period:
T = 2π / μ
(d)
|u(t)| < 0.05 cm
u(t) = |2e⁻¹⁰^t cos 4√6t + 5√6/6 e⁻¹⁰^t sin 4√6t < 0.05
solving for t:
τ = t ≈ 0.4045
The concept required to solve this problem is that related to the Isobaric process. Isobaric process is understood as the process in which changes occur at constant pressure. From the first law of thermodynamics this can be expressed as,
Here,
P = Pressure
dV = Differential of Volume
As the Pressure is constant we have,
Replacing
Therefore the correct answer is A.
Mechanical waves require matter to travel medium. If there is no substance or matter to travel through, mechanical waves cannot propagate.
Since space is mostly vacuum, there is no medium for waves to travel through: waves sent by the sun (electromagnetic waves) are not mechanical waves