I think it is B Because it sounds like the best choice
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
Question; what causes earthquakes?
Answer; what causes earthquakes are mainly when rocks are underground and then suddenly break along a fault.
Answer:
Yes.
Explanation:
Reactors use uranium for nuclear fuel. The uranium is processed into small ceramic pellets and stacked together onto sealed metal tubes called fuel rods. The heat created by fission turns the water into steam.
The moment of inertia of the flywheel is 2.63 kg-
It is given that,
The maximum energy stored on the flywheel is given as
E=3.7MJ= 3.7×
J
Angular velocity of the flywheel is 16000
= 1675.51
So to find the moment of inertia of the flywheel. The energy of a flywheel in rotational kinematics is given by :
E = 

By rearranging the equation:
I = 
I = 2.63 kg-
Thus the moment of inertia of the flywheel is 2.63 kg-
.
Learn more about moment of inertia here;
brainly.com/question/13449336
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