Answer:
The force of attraction between the molecules of the same substance
Explanation:
Answer:
v=20m/S
p=-37.5kPa
Explanation:
Hello! This exercise should be resolved in the next two steps
1. Using the continuity equation that indicates that the flow entering the nozzle must be the same as the output, remember that the flow equation consists in multiplying the area by the speed
Q=VA
for he exitt
Q=flow=5m^3/s
A=area=0.25m^2
V=Speed
solving for V
velocity at the exit=20m/s
for entry
2.
To find the pressure we use the Bernoulli equation that states that the flow energy is conserved.
where
P=presure
α=9.810KN/m^3 specific weight for water
V=speed
g=gravity
solving for P1
the pressure at exit is -37.5kPa
The correct answer is:
Work is negative, the environment did work on the object, and the energy of the system decreases.
In fact, the work-energy theorem states that the work done by the system is equal to its variation of kinetic energy:
In this problem, the variation of kinetic energy is negative (because the final velocity is less than the initial velocity), so the work is negative, and this means that the environment did work on the object, and its energy decreased.