The frequency of a beam of light does not change as it passes from a medium to another, only its wavelength and speed are affected. The experimental speed of light in air is:
3 * 10^8 m/s
Therefore, the frequency of this beam of light is:
v = fλ; where v is speed, f is frequency, and λ is the wavelength. The frequency thus is:
3×10⁸ / (670 × 10⁻⁹) = 4.48 × 10¹⁴ Hz
The frequency will remain the same in the solid medium
The speed will then become:
4.48 × 10¹⁴ × 420 × 10⁻⁹ = 1.88 × 10⁸ meters per second
Okay, passive solar is used to gain heat energy, not electricity, so that is one. All the others can be used to produce electricity, so I'm not sure what the second answer is.
Answer:
q_poly = 14.55 KJ/kg
Explanation:
Given:
Initial State:
P_i = 550 KPa
T_i = 400 K
Final State:
T_f = 350 K
Constants:
R = 0.189 KJ/kgK
k = 1.289 = c_p / c_v
n = 1.2 (poly-tropic index)
Find:
Determine the heat transfer per kg in the process.
Solution:
-The heat transfer per kg of poly-tropic process is given by the expression:
q_poly = w_poly*(k - n)/(k-1)
- Evaluate w_poly:
w_poly = R*(T_f - T_i)/(1-n)
w_poly = 0.189*(350 - 400)/(1-1.2)
w_poly = 47.25 KJ/kg
-Hence,
q_poly = 47.25*(1.289 - 1.2)/(1.289-1)
q_poly = 14.55 KJ/kg
