• At a point in a piece of material there is a tensile stress of 90 MN/m^2 upon the horizontal plane, and compressive stress of 45MN/m^2 upon the vertical plane. There is also a shear stress of 45MN/m^2 on each of these planes. Determine the planes of maximum shear stress and value of maximum shear stress at the point from the first principles.

• Mohit Singh posted an update 1 day, 15 hours ago

Good evening friends..
How are you???

• यरूशलेम में दूतावास खोलने वाला दूसरा देश कौन है ?

• ग्वाटेमाला

• But यरूशलेम में दूतावास खोलने वाला पहला देश कौन है ?

• UNITED STATE OF AMERICA

A flow of water of 100 litres per second flows down in a rectangular flume of width 600 mm and having adjustable bottom slope. If chezy’s constant C is 56, find the bottom slope necessary for uniform flow of 300 mm. Also find the conveyance K of the flume.

• Given,
Discharge, Q = 100 litres/second
= 100/1000 m^3/second …[We know that, 1 litre =1/1000 m^3] Width of the channel, b= 600 mm= 0.60 m
Depth of the channel, d = 300 mm= 030 m
So, Area of flow, A = b.d = 0.60 x 0.30 = 0.18 m^2
Chezy’s constant, C = 56
Find the slope of bed(i) = ?
Hydraulic mean depth (m) = A/P = A…[Read more]

• What is the formula of conveyance K ?

• We know that
Discharge (Q) = A.V
= A.C(m.i)^1/2 ……………………. From chezy’s formula
Which can be written as Q = K(i)^1/2
Where K = AC(m)^1/2 & K is called conveyance of the channel section.

• Conveyance of the channel : –
K=AC(m)^1/2
Where, K = Conveyance of the channel section.
A = Area of the channel
C = Chezy’s constant
m = Hydraulic mean depth or radius

• What is the formula of Froude Number in fluid mechanics?

• Fe = V/(gD)^1/2
Where,
V = mean velocity of flow
D = Hydraulic depth of channel
= A/T (wetted area/ top width of channel).

• In super critical flow the velocity of liquid is …
(1) Low
(2) Maximum
(3) Average
(4) None

• What is torrential flow?

• Mohit Singh posted an update 2 weeks, 2 days ago

hello frnds…

• For solar collectors, what combination of surface characteristics is required ?
(1) High absorptivity and high reflectivity
(2) High reflectivity & high emissivity

• On which of the following factors does the emissive power of a body depend ?
(1) Wavelength
(2) Temperature
(3) Physical nature
(4) All of the above

• On which of the following factors does the amount of radiation mainly depend
(1) Temp. of body
(2) Type of surface of body
(3) Nature of body
(4) All of the above

• The emissivity is likely to be higher in case of
(1) Iron oxide
(2) Paper
(3) Carbon
(4) Rubber

• In which of the following cases, heat transfer by radiation is encountered least?
(1) Electric bulb
(2) Nuclear reactor
(3) Boiler furnace
(4) Insulated steam pipe

• According to Wien’s law, the wavelength corresponding to maximum energy is proportional to..
(1) T
(2) T^2
(3) T^3
(4) T^4

• (1) T

• Wien’s Law: – It states that the wavelength corresponding to the maximum energy is inversely proportional to the absolute temp. of the hot body.

• Which of the following properties of air does not increase with rise in temp?
(1) Thermal diffusivity
(2) Dynamic viscosity
(3) Density
(4) Thermal conductivity

• The temp. of sun can be measured by using a
(2) standard thermometer
(3) mercury thermometer
(4) none of the above

• The intensity of solar radiation on earth is..
(1) 1 kW/m^2
(2) 2 kW/m^2
(3) 4 kW/m^2
(4) 8 kW/m^2

• What is the concept of black body ??

• is a theoretically ideal radiator and absorber of energy at all electromagnetic wavelengths. The term comes from the fact that a cold blackbody appears visually black.The energy emitted by a blackbody is called blackbody radiation.

• A black body is an object that absorbs all radiant energy reaching its surface. The concept of a black body is an idealization with which the radiation characteristics of real body can be conveniently compared.

• Heat transfer from higher temp. to low temp. takes place according to
(1) Fourier law
(2) First law of thermodynamics
(3) second law of thermodynamics
(4) zeroth law of thermodynamics