Answer:

& 
Explanation:
Given:
- interior temperature of box,

- height of the walls of box,

- thickness of each layer of bi-layered plywood,

- thermal conductivity of plywood,

- thickness of sandwiched Styrofoam,

- thermal conductivity of Styrofoam,

- exterior temperature,

<u>From the Fourier's law of conduction:</u>

....................................(1)
<u>Now calculating the equivalent thermal resistance for conductivity using electrical analogy:</u>




.....................(2)
Putting the value from (2) into (1):


is the heat per unit area of the wall.
The heat flux remains constant because the area is constant.
<u>For plywood-Styrofoam interface from inside:</u>



&<u>For Styrofoam-plywood interface from inside:</u>



If the applied force is in the same direction as the object's displacement, the work done on the object is:
W = Fd
W = work, F = force, d = displacement
Given values:
F = 45N
d = 12m
Plug in and solve for W:
W = 45(12)
W = 540J
Answer:
the color is green
- 602.93 nm ( orange color )
the observation is that there is a change of visible color
Explanation:
A) wavelength of visible light that is most strongly reflected from a point on a soap
refraction n = 1.33
wall thickness (t) = 290 nm
2nt = (2m +1 ) ∝/2 -----equation 1
note when m = 0
therefore ∝ = 4nt/ 1 = 4 * 1.33 * 290 = 1542.8nm we will discard this
when m = 1
equation 1 becomes
∝ = 4nt/3 =( 4 * 1.33 * 290) / 3 = 1542.8 / 3 = 514.27 ( wavelength )
the color is green
B) the wavelength when the wall thickness is 340 nm
∝ = 4nt / 2m +1
where m = 1
∝ = (4 * 1.33 * 340 ) / 3 = 1808.8 / 3 = 602.93 nm ( orange color )
the observation is that there is a change of visible color
1. GPE - 40 * 2 * 10 = 800j