Answer:
Explanation:
Basically, the point on the axis of a lens or mirror to which parallel rays of light converge or from which they appear to diverge after refraction or reflection.
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Answer:
Energy Level..........................................................................................
Risks are only in a persons
Answer:
Heat transfer during the process = 0
Work done during the process = - 371.87 KJ
Explanation:
Initial pressure
= 0.02 bar
Initial temperature
= 200 K
Final pressure
= 0.14 bar
Gas constant for helium R = 2.077 
This is an isentropic polytropic process so temperature - pressure relationship is given by the following formula,
= ![[\frac{P_{2} }{P_{1} } ]^{\frac{\gamma - 1}{\gamma} }](https://tex.z-dn.net/?f=%5B%5Cfrac%7BP_%7B2%7D%20%7D%7BP_%7B1%7D%20%7D%20%5D%5E%7B%5Cfrac%7B%5Cgamma%20-%201%7D%7B%5Cgamma%7D%20%7D)
Put all the values in above formula we get,
⇒
= ![[\frac{0.14 }{0.02 } ]^{\frac{1.4 - 1}{1.4} }](https://tex.z-dn.net/?f=%5B%5Cfrac%7B0.14%20%7D%7B0.02%20%7D%20%5D%5E%7B%5Cfrac%7B1.4%20-%201%7D%7B1.4%7D%20%7D)
⇒
= 1.74
⇒
= 348.72 K
This is the final temperature of helium.
For isentropic polytropic process heat transfer to the system is zero.
⇒ ΔQ = 0
Work done W = m × (
-
) × 
⇒ W = 1 × ( 200 - 348.72 ) × 
⇒ W = 371.87 KJ
This is the work done in this process. here negative sign shows that work is done on the gas in the compression of gas.
"Watch" . . . atmospheric conditions exist that could
produce tornados, but none have been seen yet.
"Warning" . . . tornados have formed and have been seen.