Hot combustion gases are accelerated in a 92% efficient
adiabatic nozzle from low velocity to a specified velocity. The exit velocity
and the exit temp are to be determined.
Given:
T1 = 1020 K à
h1 = 1068.89 kJ/kg, Pr1 = 123.4
P1 = 260 kPa
T1 = 747 degrees Celsius
V1 = 80 m/s ->nN = 92% -> P2
= 85 kPa
Solution:
From the isentropic relation,
Pr2<span> = (P2 / P1)PR1 = (85
kPa / 260 kPa) (123.4) = 40.34 = h2s = 783.92 kJ/kg</span>
There is only one inlet and one exit, and thus, m1 =
m2 = m3. We take the nozzle as the system, which is a
control volume since mass crosses the boundary.
h2a = 1068.89 kJ/kg – (((728.2 m/s)2 –
(80 m/s)2) / 2) (1 kJ/kg / 1000 m2/s2) =
806.95 kJ/kg\
From the air table, we read T2a = 786.3 K
We can solve the problem by using Snell's law, which states
where
is the refractive index of the first medium
is the angle of incidence
is the refractive index of the second medium
is the angle of refraction
In our problem,
(refractive index of air),
and
(refractive index of carbon disulfide), therefore we can re-arrange the previous equation to calculate the angle of refraction:
From which we find
Answer:
A) B = 9.425 × 10^(-5) T
B) North direction
Explanation:
A) We are given;
Current in coil; I = 4.5 A
Number of turns; N = 100 turns
Radius;R = diameter/2 = 6/2 = 3 m
Formula for the magnetic field at the center of the coil is given by;
B = (μ_o•N•I)/2R
Where μ_o is a constant = 4π × 10^(-7) H/m
Thus;
B = (4π × 10^(-7) × 100 × 4.5)/(2 × 3)
B = 9.425 × 10^(-5) T
B) The direction of the force on a positive ion in water can be gotten by the application of flemmings right hand rule.
From flemmings right hand rule, we know that;
- The thumb indicates the direction of the motion of the force which is in the north direction.
- The Index finger indicates the direction of the magnetic field which is in the east direction
- The middle finger indicates the direction of magnetic field which is downwards in the west direction.
Therefore, the direction of the force as seen from flemmings right hand rule is in the north direction
<span>work will be equal to the potential energy gained by the person in climbing the stairs.
work= potential energy gained = mgh
W= 75kg*9.8m/s2*2.50m= 1837.5 J</span>
Answer:
The value is 
Explanation:
From the question we are told that
The speed of the marathon runner is 
The distance from the distance from the finish is 
The speed of the bird is 
Generally the time taken for the runner to reach the finish is mathematically represented as
So the distance covered by the bird is
