Answer:
Outside temperature =88.03°C
Explanation:
Conductivity of air-soil from standard table
K=0.60 W/m-k
To find temperature we need to balance energy
Heat generation=Heat dissipation
Now find the value
We know that for sphere
![q=\dfrac{2\pi DK}{1-\dfrac{D}{4H}}(T_1-T_2)](https://tex.z-dn.net/?f=q%3D%5Cdfrac%7B2%5Cpi%20DK%7D%7B1-%5Cdfrac%7BD%7D%7B4H%7D%7D%28T_1-T_2%29)
Given that q=500 W
so
![500=\dfrac{2\pi 2\times .6}{1-\dfrac{2}{4\times 10}}(T_1-25)](https://tex.z-dn.net/?f=500%3D%5Cdfrac%7B2%5Cpi%202%5Ctimes%20.6%7D%7B1-%5Cdfrac%7B2%7D%7B4%5Ctimes%2010%7D%7D%28T_1-25%29)
By solving that equation we get
=88.03°C
So outside temperature =88.03°C
Answer:
μ=0.329, 2.671 turns.
Explanation:
(a) ln(T2/T1)=μβ β=angle of contact in radians
take T2 as greater tension value and T1 smaller, otherwise the friction would be opposite.
T2=5000 lb and T1=80 lb
we have two full turns which makes total angle of contact=4π radians
μ=ln(T2/T1)/β=(ln(5000/80))/4π
μ=0.329
(b) using the same relation as above we will now compute the angle of contact.
take greater tension as T2 and smaller as T1.
T2=20000 lb T1=80 lb μ=0.329
β=ln(20000/80)/0.329=16.7825 radians
divide the angle of contact by 2π to obtain number of turns.
16.7825/2π =2.671 turns
Answer:
2.8
Explanation:
The ideal mechanical advantage of the pulley IMA = D'/D where D' = diameter of output pulley = 7 inches and D = diameter of input pulley = 2.5 inches
So, IMA = D'/D
= 7/2.5
= 2.8
So, the ideal mechanical advantage of the pulley IMA = 2.8
Answer: c) they have low genetic variability among them.
When a plant is grown for several generations of offspring of a plant, then there are some common things which are to be noted which are found similar in the offspring and in the parent of the offspring. The flowers and fruits and the time or season they come in are absolutely the same.
Answer:
8861.75 m approximately 8862 m
Explanation:
We need to remember Newton's 2nd Law which says that the force experienced by an object is proportional to his acceleration and that the constant of proportionality between those two vectors correspond to the mass of the object.
for the weight of an object (which is a force) we have that the acceleration experienced by that object is equal to the gravitational acceleration, obtaining that ![W = mg](https://tex.z-dn.net/?f=W%20%3D%20mg)
For simplicity we work with
despiting the effect of the height above sea level. In this problem, we've been asked by the height above sea level that makes the weight of an object 0.30% more lighter.
In accord with the formula
the "normal" or "standard" weight of an object is given by
when
, so we need to find the value of
that makes
meaning that the original weight decrease by a 0.30%, so now we operate...
now we group like terms on the same sides
we cancel equal tems on both sides and obtain that ![z = \frac{a}{b} (0.003) = \frac{9.807 \frac{m}{s^{2} } }{3.32*10^{-6} s^{-2} } (0.003) = 8861.75 m](https://tex.z-dn.net/?f=z%20%3D%20%5Cfrac%7Ba%7D%7Bb%7D%20%280.003%29%20%3D%20%5Cfrac%7B9.807%20%5Cfrac%7Bm%7D%7Bs%5E%7B2%7D%20%7D%20%7D%7B3.32%2A10%5E%7B-6%7D%20s%5E%7B-2%7D%20%7D%20%280.003%29%20%3D%208861.75%20m)