:<span> </span><span>Under the assumption that a cell is made up of two concentric spheres you find the surface are of the inside sphere which will be your A.
You already have your separation and dielectric constant so just use the formula you stated towards the end of your question and you get 8.93x10^-11 Farads which is about 89pF</span>
We know that the acceleration due to gravity g is: g =
9.81 m/s^2
So the centripetal acceleration (w) is:
w^2 = 1.5 g / r
w^2 = 1.5 * (9.81 m/s^2) / 5 m
w = 1.716 rad / s
To convert to rad to rev:
w = (1.716 rad / s) * (1 rev / 2π rad) * (60 s/min)
<span>w = 16.4 rev/min </span>
Answer:
r₂ = 0.316 m
Explanation:
The sound level is expressed in decibels, therefore let's find the intensity for the new location
β = 10 log
let's write this expression for our case
β₁ = 10 log \frac{I_1}{I_o}
β₂ = 10 log \frac{I_2}{I_o}
β₂ -β₁ = 10 (
)
β₂ - β₁ = 10
log \frac{I_2}{I_1} =
= 3
= 10³
I₂ = 10³ I₁
having the relationship between the intensities, we can use the definition of intensity which is the power per unit area
I = P / A
P = I A
the area is of a sphere
A = 4π r²
the power of the sound does not change, so we can write it for the two points
P = I₁ A₁ = I₂ A₂
I₁ r₁² = I₂ r₂²
we substitute the ratio of intensities
I₁ r₁² = (10³ I₁ ) r₂²
r₁² = 10³ r₂²
r₂ = r₁ / √10³
we calculate
r₂ =
r₂ = 0.316 m