Answer:
t = 4.0 min
Explanation:
given data:
diameter of rod = 2 cm
T_1 = 100 degree celcius
Air stream temperature = 20 degree celcius
heat transfer coefficient = 200 W/m2. K
WE KNOW THAT
copper thermal conductivity = k = 401 W/m °C
copper specific heat Cp = 385 J/kg.°C
density of copper = 8933 kg/m3
charateristic length is given as Lc
Biot number is given as 
Bi = 0.0025
As Bi is greater than 0.1 therefore lumped system analysis is applicable
so we have
............1
where b is given as
b = 0.01163 s^{-1}
putting value in equation 1
solving for t we get
t = 4.0 min
Answer
Given,
refractive index of film, n = 1.6
refractive index of air, n' = 1
angle of incidence, i = 35°
angle of refraction, r = ?
Using Snell's law
n' sin i = n sin r
1 x sin 35° = 1.6 x sin r
r = 21°
Angle of refraction is equal to 21°.
Now,
distance at which refractive angle comes out
d = 2.5 mm
α be the angle with horizontal surface and incident ray.
α = 90°-21° = 69°
t be the thickness of the film.
So,
t = 2.26 mm
Hence, the thickness of the film is equal to 2.26 mm.
Answer:
waves
Explanation:
There are three major ways in which heat or thermal energy is transferred namely: conduction, convection and radiation. Please find the description of each below;
- Conduction is the method of heat transfer which involves a physical contact between the substances involved.
- Convection, on the contrary, occurs via a liquid medium
- RADIATION is a method of heat transfer which involves neither physical contact or liquid medium (matter) but occurs through WAVES e.g electromagnetic waves. For example, the sun transfers heat to the Earth via RADIATION.
Those organic structures that do not seem to play any important biological function in the organism that possesses them are known as vestigial structures.
<h2>What is a vestigial structure?</h2>
A vestigial structure is one that has atrophied or lost its original function throughout the course of evolution.
- It generally refers to those organic structures that were useful at some point, but are now practically or totally useless.
- These structures are preserved as an inheritance of the evolutionary process, because at some point an ancestor of the current species had that structure, which was functional, but it ceased to be important and would end up atrophy.
Therefore, we can conclude that vestigial structures are structures that some organisms still conserve as an inheritance from their ancestors but that, for some reason or another, are no longer useful for the functioning of the same.
Learn more about vestigial structures here: brainly.com/question/2141655
