A unit for measuring frequency, equal to one cycle per second. If a sound wave has a frequency of 20,000 Hz, this means that 20,000 waves are passing through a given point during the interval of one second.
Answer:
F = GMm / r²
from Newton's law of gravitational attraction
Answer:
T_t = Ts (1-A √ (Rs/D)
Explanation:
The black body radiation power is given by Stefan's law
P = σ A e T⁴
This power is distributed over a spherical surface, so the intensity of the radiation is
I = P / A
Let's apply these formulas to our case. Let's start by calculating the power emitted by the Sun, which has an emissivity of one (e = 1) black body
P_s = σ A_s 1 T_s⁴
This power is distributed in a given area, the intensity that reaches the earth is
I = P_s / A
A = 4π R²
The distance from the Sun Earth is R = D
I₁ = Ps / 4π D²
I₁ = σ (π R_s²) T_s⁴ / 4π D²
I₁ = σ T_s⁴ R_s² / 4D²
Now let's calculate the power emitted by the earth
P_t = σ A_t (e) T_t⁴
I₂ = P_t / A_t
I₂ = P_t / 4π R_t²2
I₂ = σ (π R_t²) T_t⁴ / 4π R_t²2
I₂ = σ T_t⁴ / 4
The thermal equilibrium occurs when the emission of the earth is equal to the absorbed energy, the radiation affects less the reflected one is equal to the emitted radiation
I₁ - A I₁ = I₂
I₁ (1 - A) = I₂
Let's replace
σ T_s⁴ R_s²/4D² (1-A) = σ T_t⁴ / 4
T_s⁴ R_s² /D² (1-A) = T_t⁴
T_t⁴ = T_s⁴ (1-A) (Rs / D) 2
T_t = Ts (1-A √ (Rs/D)
Answer:
If the rod is swapped for a different material such as acetate , electrons are rubbed off the acetate and onto the duster. The acetate rod has lost electrons, giving it a positive charge. The duster has gained electrons, giving it a negative charge.
Brainliest would be nice
B). A <span>car that rounds a curve at a constant speed is accelerating.
</span><span>D). A car that is set to a constant speed of 60 miles per hour is
accelerating IF the road ever curves. </span><span>
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