Answer:
a) , b) , c) 1600
Explanation:
a) The Reynolds Number is modelled after the following formula:
Where:
- Fluid density.
- Dynamics viscosity.
- Diameter of the tube.
- Fluid speed.
The formula can be expanded as follows:
b) The Reynolds Number has this alternative form:
c) Since the diameter is the same than original tube, the Reynolds number is 1600.
Answer:
5040 watts
Explanation:
Power (P) = electric current (I) × Time (T)
P = 400 × 12.6
P = 5040 watts
Answer:
T=833.8 °C
Explanation:
Given that
m= 2 kg
T₁=200 °C
time ,t= 10 min = 600 s
Work input = 1 KW
Work input = 1 x 600 KJ=600 KJ
Heat input = 0.5 KW
Q= 05 x 600 = 300 KJ
Gas is ideal gas.
We know that for ideal gas internal energy change given as
ΔU= m Cv ΔT
For air Cv= 0.71 KJ/kgK
From first law of thermodynamics
Q = ΔU +W
Heat input taken as positive and work in put taken as negative.
300 KJ = - 600 KJ + ΔU
ΔU = 900 KJ
ΔU= m Cv ΔT
900 KJ = 2 x 0.71 x (T- 200 )
T=833.8 °C
So the final temperature is T=833.8 °C
Answer:
Q=0.00274 Lt/s
Explanation:
Given that
Darcy friction factor f=0.04
Diameter of pipe d=10 mm
We know that for laminar flow
Where Re is the Reynolds number and f is the friction factor.
Now by putting the values
Re=400
We know that
for water
V=0.035 m/s
So volume flow rate Q=AV
Q=0.00274 Lt/s
Answer:critical stress= 20.23 MPa
Explanation:
Since there was an internal crack, we will divide the length of the internal crack by 2
Length of internal crack, a = 0.7mm,
Half length = 0.7mm/2= 0.35mm changing to meters becomes
0.35/ 1000= 0.35 x 10 ^-3m
The formulae for critical stress is calculated using
σC = (2Eγs /πa) ¹/₂
σC = critical stress=?
Given
E= Modulus of Elasticity= 225GPa =225 x 10 ^ 9 N/m²
γs= Specific surface energy = 1.0 J/m2 = 1.0 N/m
a= Half Length of crack=0.35 x 10 ^-3m
σC= (2 x 225 x 10 ^ 9 N/m² x 1.0 N/m /π x 0.35 x 10 ^-3m)¹/₂
=(4.5 x 10^11/π x 0.35 x 10 ^-3)¹/₂
=(4.0920 x10 ^14)¹/₂
σC=20.23 x10^6 N/m² = 20.23 MPa