I think the best answer would be the last option. The main purpose of a service panel in a house is to keep electrical hazards localized. Service panels are used to identify circuit loads and isolate these loads so when you want to check the equipment you can easily identify the line. Also, it would serve as the isolation point to avoid any electrical hazards.
Answer:
Explanation:
a. Internal energy and the relative specific volume at 
are determined from A-17:
.
The relative specific volume at 
is calculated from the compression ratio:
#from this, the temperature and enthalpy at state 2, can be determined using interpolations 
and 
. The specific volume at can then be determined as:
Specific volume,:
The pressures at 
is:
.The thermal efficiency=> maximum temperature at 
can be obtained from the expansion work at constant pressure during 
b.Relative SV and enthalpy at are obtained for the given temperature with interpolation with data from A-17 :
Relative SV at 
is
=
Thermal efficiency occurs when the heat loss is equal to the internal energy decrease and heat gain equal to enthalpy increase;
Hence, the thermal efficiency is 0.563
c. The mean relative pressure is calculated from its standard definition:
Hence, the mean effective relative pressure is 674.95kPa
Answer: a) 7.1 * 10^3 N; b) -880 N directed out of the curve.
Explanation: In order to solve this problem we have to use the Newton laws, then we have the following:
Pcos 15°-N=0
Psin15°-f= m*ac
from the first we obtain N, the normal force
N=750Kg*9.8* cos (15°)= 7.1 *10^3 N
Then to calculate the frictional force (f) we can use the second equation
f=P sin (15°) -m*ac where ac is the centripetal acceletarion which is equal to v^2/r
f= 750 *9.8 sin(15°)-750*(85*1000/3600)^2/150= -880 N
