Answer:
The vacuum tube was replaced with transistor.
Explanation:
- The invention of semiconductor was very useful in making solid state transistor that allowed the production of small yet faster, cheaper, and more trusted and reliable computers.
- These solid state transistor is so often used that, it nearly replaced all the use of transistor.
- This replacement took place after the invention of semiconductor in the year around 1940.
- Vacuum tubes also known as thermionic tubes are not used anymore in computers and electronics.
Answer:
Energy loss per minute will be 
Explanation:
We have given the star produces power of 
We know that 1 W = 1 J/sec
So 
Given time = 1 minute = 60 sec
So the energy loss per minute 
We multiply with 60 we have to calculate energy loss per minute
The answer to the blank is physical.
Answer:
Temperature : 92.9 F
Internal Energy change: -2.53 Btu/lbm
Explanation:
As
mh1=mh2
h1=h2
In table A-11 through 13E
p2=120Psi, h1= 41.79 Btu/lbm,
u1=41.49
So T1=90.49 F
P2=20Psi
h2=h1= 41.79 Btu/lbm
T2= -2.43F
u2= 38.96 Btu/lbm
T2-T1 = 92.9 F
u2-u1 = -2.53 Btu/lbm