Answer:
warmer
Explanation:
The law of conservation of energy tells us that energy cannot be created or destroyed, it can be transferred or converted from one from to another. In this question when the beer that is at room temperature is put in the fridge, it loses some heat energy. This heat energy is not destroyed, the fridge through multiple processes eventually releases this heat to the room through pipes at the back which is why they are normally warm. the heat from the food inside is expelled to the room. It is not lost.
Answer:
Inverted (displaced downwards)
Explanation:
The pulse becomes INVERTED upon reflecting off the boundary with the wall. That is, an upward-displaced pulse will reflect off the end and return with a downward displacement. This inversion behavior will always be observed when the end of the medium is fixed, like this wall in this instance. This INVERSION BEHAVIOR can also be observed when the medium is connected to another more heavy or more dense medium. And in this case, when the pulse reaches the end of the medium, a portion of the pulse will reflect off the end and return with an inverted displacement. The heavier medium acts like a fixed end to cause the pulse to be inverted.
Summary: a pulse reaching the end of a medium becomes inverted whenever it either:
i. reflects off a fixed end,
ii. is moving in a less dense medium and reflects off a more dense medium.
Answer:
Total heat transfer rate is combined convection and radiation transfer rate, multiplied with absorptivity factor. From that equation you can find temperature of the roof using iteration method.
Explanation:
<u>Known:</u>
steel sheet roof emissivity ∈ = 0.13
steel sheet roof absorptivity _s = 0.65
air temperature T∞ = 16°C ...= 289K
heat transfer rate = 750 W/m2
natural convection h = 7W/m2K
Total heat transfer rate is combined heat transfer rate of convection and radiation, multiplied with absorptivity factor:
=T∞-)+∈σA(
-T∞)-∈σ(=0
2562-7-7.371*10^-9=0
Use iteration method to solve for
=350.17 K...=77.17°C
In this particular situation, cat would not be comfortable with walking on a roof since its surface temperature is 77.17°C which may even cause burns to its paws.
The magnetic flux through an area A is given by
where
B is the magnitude of the magnetic field
A is the area
is the angle between the direction of B and the perpendicular to the surface A.
In our problem, the area lies in the x-y plane, while B is in the z direction, this means that B and the perpendicular to A are parallel, so
and
, so we can rewrite the formula as
We can calculate the area starting from the radius:
And then using the intensity of the magnetic field given by the problem,
, we find the magnetic flux: