Answer:
k=0.0577w/mk
k=0.03338BTU/h-ft-ºF
Explanation:
First we use the equation for heat transfer by conduction and solve for K
Q=KA(T2-T1)/x
Where
q=heat
A=area
T=temperature
K=conductivity
x=thickness
solving for k
k=Qx/A(T2-T1)
Q/A=Heat flux=q
k=qx/(T2-T1)
k=35.1*0.025/(318.4-303.2)
K=0.0577w/mk
remember that 1 btu / hftk equals 1,729 w / mk
K=0.0577/1.729=0.03338BTU/h-ft-ºF
Since the temperature decreases (cold) , the pressure exerted will decrease. the particles are move slower and collide less vigorously and frequently with the inner surface of the container . therefore since p = f/a , the pressure will decrease as force exerted decreases .
Answer:
Explanation:
To identify forces acting on an object
1. Draw a closed curve around the system.
2.Identify "the system" and "the environment."
3. Draw a picture of the situation. Which of these are steps used to identify the forces acting on an object?
All of these are correct.
A close loop doesn't allow external forces to act on the system and this only allows the the forces on the object to act alone.
Drawing the free body diagram will show the forces acting on the body.
Also, isolating the system from the environment so that it won't be affected by external forces or resistance
Answer:
B. They usually need to be cooled to dissipate thermal energy build-up and prevent damage.
Explanation:
High energy mechanical devices needs to be cooled down because they have moving parts which creates heat which may affect the other electrical and electronic component of the device. Because quality of material changes with the temperature. If high temperature occur might change the shape of that component and may affect the efficiency of the machine.
