Answer:
The velocity at R/2 (midway between the wall surface and the centerline) is given by (3/4)(Vmax) provided that Vmax is the maximum velocity in the tube.
Explanation:
Starting from the shell momentum balance equation, it can be proved that the velocity profile for fully developedblaminar low in a circular pipe of internal radius R and a radial axis starting from the centre of the pipe at r=0 to r=R is given as
v = (ΔPR²/4μL) [1 - (r²/R²)]
where v = fluid velocity at any point in the radial direction
ΔP = Pressure drop across the pipe
μ = fluid viscosity
L = pipe length
But the maximum velocity of the fluid occurs at the middle of the pipe when r=0
Hence, maximum veloxity is
v(max) = (ΔPR²/4μL)
So, velocity at any point in the radial direction is
v = v(max) [1 - (r²/R²)]
At the point r = (R/2)
r² = (R²/4)
(r²/R²) = r² ÷ R² = (R²/4) ÷ (R²) = (1/4)
So,
1 - (r²/R²) = 1 - (1/4) = (3/4)
Hence, v at r = (R/2) is given as
v = v(max) × (3/4)
Hope this Helps!!!
Answer:
Volume is not the fundamental dimension. So, option d is correct.
Explanation:
Step1
Fundamental dimension is the dimension in which other quantities depend. These are the basic dimensions. Three basic fundaments dimensions are mass, length and time that is represented as MLT respectively.
Step2
Volume is not the fundamental dimension among them as the volume is cube of length dimension. Thus, volume depends upon length.
Thus, Volume is not the fundamental dimension. So, option d is correct.
Answer:
1839
Explanation:
the first huge step in solar penal technology came when alxendare becquerel observed the photovolatic effect in 1839,which occurs when a material produces electric current when exposed to light.it was not untill 1888 that the first solar cell was actually built by aleksander stoletov.
Answer:
Q = 5.06 x 10⁻⁸ m³/s
Explanation:
Given:
v=0.00062 m² /s and ρ= 850 kg/m³
diameter = 8 mm
length of horizontal pipe = 40 m
Dynamic viscosity =
μ = ρv
=850 x 0.00062
= 0.527 kg/m·s
The pressure at the bottom of the tank is:
P₁,gauge = ρ g h = 850 x 9.8 x 4 = 33.32 kN/m²
The laminar flow rate through a horizontal pipe is:
Q = 5.06 x 10⁻⁸ m³/s
Answer:
i)ω=3600 rad/s
ii)V=7059.44 m/s
iii)F=1245.8 N
Explanation:
i)
We know that angular speed given as
We know that for one revolution
θ=2π
Given that time t= 2 hr
So
ω=θ/t
ω=2π/2 = π rad/hr
ω=3600 rad/s
ii)
Average speed V
Where M is the mass of earth.
R is the distance
G is the constant.
Now by putting the values
V=7059.44 m/s
iii)
We know that centripetal fore given as
Here given that m= 200 kg
R= 8000 km
so now by putting the values
F=1245.8 N