A solar panel occupies the region bounded by y = 1 − x^4 and y = 0 (length units in meters). Suppose the power density of sunlight hitting the panel is P(x, y) = 1000 (1 − y/2) watts/m2 . Find the total power hitting the panel. How much energy (Joules) does the panel receive in 8 hours? (1 watt = 1 Joule/sec)

Respuesta :

Answer:

P = 1162 W

E =  33 476 923 Joules

Explanation:

Hi, to calculate the total power hitting the panel we must integrate the power density P(x,y) inside the panel area, that is:

[tex]P = \int\limits^{x=1}_{x=-1} \int \limits^{y=1-x^4}_{y-0} {P(x,y)}\, dxdy\\[/tex]

First we integrate the y variable since is the dependent variable for the present problem.

[tex]P = 1000W\int\limits^{x=1}_{x=-1} {(y' - \frac{y'^3}{3})\limits^{y'=1-x^4}_{y'=0}} \, dx\\\\\\P= 1000W \int\limits^{x=1}_{x=-1} {(1-x^4 - \frac{(1-x^4)^3}{3})} \, dx[/tex]

The integral is pretty straigthfoward, but involves expanding the binomial.

However the answer is:

[tex]P = 1000W \frac{1}{3} (\frac{x^{13} }{13} - \frac{x^{-9}}{3} +2x)\limits^{x=1}_{x=-1}\\\\P = 1000 \frac{136}{117} W[/tex]

That is:

P = 1162 W

Since 1W = 1J/1s

The total energy recieved in 8 hours will be:

E = P*(8*3600 s)

E = 33 476 923 Joules