Answer:
The change in kinetic energy is 4.3875 kJ
The amount of energy transferred by heat for the process is -66.98 kJ
Explanation:
Given;
mass of the system, m = 13 kg
change in height, Δh = -50 m
initial velocity, u = 15 m/s
final velocity, v = 30 m/s
change in internal energy per mass, ΔU = -5 kJ/kg
The change in kinetic energy is given by;
ΔK.E = K.E₂ - K.E₁
ΔK.E = ¹/₂mv² - ¹/₂mu²
ΔK.E = ¹/₂m(v² - u²)
ΔK.E = ¹/₂ ₓ 13 (30² - 15²)
ΔK.E = 4387.5 J
ΔK.E = 4.3875 kJ
The amount of energy transferred by heat for the process;
Q = W + ΔP.E + ΔK.E + ΔU
Where;
ΔP.E = mgΔh
ΔP.E = 13 x 9.8 x (-50)
ΔP.E = -6370 J = -6.37 kJ
W = 0
ΔU = -5kJ/kg x 13kg
ΔU = -65 kJ
Q = W + ΔP.E + ΔK.E + ΔU
Q = 0 + (-6.37) + (4.3875) + (-65)
Q = -66.98 kJ
Yaaaas, do you watch James Charles!?
The answer is B. The nuclei of elements.
Answer:
a) 20 nodes b) zero nodes
Explanation:
When we have standing waves in a bend we have nodes at the ends and the equation describes the number of possible waves in the string is
L = n λ/2
Where λ is the wavelength, L is the length of the string, in our case it would be D and n is an entered. We can strip the wavelength of this expression
λ = 2L / n
Let's calculate what value of n we have for a wavelength equal to D/10
λ = 2D / n
λ = D / 10
We match and calculate
2D / n = D / 10
2 / n = 1/10
n = 20
Perform them for λ = D / 20
λ = 2D / n
2D / n = D / 20
n = 2 20 = 40
Since n is an inter there should be a wavelength for each value of n in the bone period there should be 20 different wavelengths
B) for La = 10D
2D / n = 10D
1 / n = 5
n = 1/5 = 0.2
La = 20D
2D / n = 20D
1 / n = 10
n = 1/10 = 0.1
These numbers are not entered so there can be no wave in this period
