Answer: 116 calories of energy
Explanation:
A calorie is a non-standard unit of energy.
On combustion,
1 gram Carbohydrates = 4 calories,
1 gram protein = 4 calories,
1gram fat = 9 calories.
Therefore,
15 grams of carbohydrates = (15*4) = 60
5 grams of protein = (5*4) = 20
4 grams of fats = (4*9) = 36
Then add up: 60 + 20 + 36 = 116 calories of energy
I = average intensity of sunlight reaching at Madison = 2000 Js⁻¹m⁻²
A = area on which the light strike = 4.80 cm² = 4.80 x 10⁻⁴ m²
energy received per second by the area is given as
E = IA
inserting the values
E = (2000) (4.80 x 10⁻⁴)
E = 0.96 J
λ = wavelength of the photons in the sunlight = 510 x 10⁻⁹ m
c = speed of light = 3 x 10⁸ m/s
h = plank's constant = 6.63 x 10⁻³⁴ J-s
n = number of photons received per second
energy received per second is also given as
E = n h c /λ
inserting the values
0.96 = n (6.63 x 10⁻³⁴) (3 x 10⁸) /(510 x 10⁻⁹)
n = 2.5 x 10¹⁸ per second
