Answer:
Massachusetts Institute of Technology (MIT)
, Stanford University, University of California, Berkeley (UCB)
Answer:
Explanation:
Let's use Shockley ideal diode equation which relates the current intensity and the potential difference:
Where:
Thermal voltage at any temperature it is a known constant defined by:
Where:
(a)
Using the data provided:
(b)
Using the data provided and Shockley ideal diode equation
(c) Let's isolate from Shockley ideal diode equation:
Finally, using the data provided:
Answer:
a) a = - 0.0524 m/s²
b) t = 6.17 s
Explanation:
Given
τ = 0.18*τ₀ / x
τ₀ = 3.6 m/s
Determine:
a) The acceleration of the air at x= 2m.
Knowing
a = dτ / dt
Multiplying both the numerator and denominator by dx
a = (dτ / dx) (dx / dt)
Substituting τ for dx / dt
a = τ*(dτ / dx)
⇒ a = τ*(-0.18*τ₀ / x²) = (0.18*τ₀ / x)(-0.18*τ₀ / x²)
⇒ a = - 0.18²*τ₀² / x³ = - 0.18²*(3.6)² / x³
⇒ a = - 0.4199 / x³
If x = 2m
⇒ a = - 0.4199 / (2)³
⇒ a = - 0.0524 m/s²
b) The time required for the air to flow from x=1 to x= 3m.
If
τ = dx / dt = 0.18*τ₀ / x
⇒ dt = (x / 0.18*τ₀) dx
⇒ t = (1 / 0.18*τ₀) ∫x dx
⇒ t = (1 / 0.18*τ₀)*(1 / 2)*x²
then
t = (1 / (0.18*3.6))*(1 / 2)*((3)² - (1)²)
⇒ t = 6.17 s