Hydraulics, Electricity, Acoustics, Lighting And Thermal Studies
Hydraulics, Electricity, Acoustics, Lighting And Thermal Studies
Hydraulics, Electricity, Acoustics, Lighting and Thermal Studies
During a thunderstorm 50 mm of rain falls. What is the weight of water falling per hectare?
Because of the finite supply of fossil fuels and the high cost of energy, the need to design energy-efficient buildings that are also economical becomes important. Various industry groups are continually updating and refining energy conservation standards and guidelines for use in the design of new buildings. These standards and guidelines may be used to assist the building designers. The designer is confronted with the fact that no two buildings are exactly identical, nor are the methods or modes of operation similar. Thus, the energy performance of each building, as a whole, must be evaluated relative to the real performance of its materials, systems and equipment.
The absolute pressure in a water pipe is 3.1 bar. When the gauge pressure is doubled the absolute pressure in the pipe is 5.1 bar. What is atmospheric pressure?
There are two different equations for computing the average pressure at various height regimes below 86 km (53 mi; 280,000 ft). Equation 1 is used when the value of standard temperature lapse rate is not equal to zero and equation 2 is used when standard temperature lapse rate equals zero.
Equation 1:
Equation 2:
where
Pb = Static pressure (pascals, Pa)
Tb = Standard temperature (kelvins, K)
Lb = Standard temperature lapse rate (kelvins per meter, K/m)
h = Height above sea level (meters, m)
hb = Height at bottom of layer b (meters; e.g., h1 = 11,000 m)
R * = Universal gas constant: 8.31447 J/(K·mol)
g0 = Standard gravity (9.80665 m/s2)
M = Molar mass of Earth's air (0.0289644 kg/mol)
A student with weight 750 N says that he can climb a set of stairs which rise 8.0 m vertically in 2.9 sec. Do you believe his claim - explain?
The earliest headlamps were fueled by acetylene or oil and were introduced in the late 1880s. Acetylene lamps were popular because the flame was resistant to wind and rain. The first electric headlamps were introduced in 1898 on the Columbia Electric Car from the Electric Vehicle Company of Hartford, Connecticut, and were optional. Two factors limited the widespread use of electric headlamps: the short life of filaments in the harsh automotive environment, and the difficulty of producing dynamos small enough, yet powerful enough to produce sufficient current. "Prest-O-Lite" acetylene lights were offered by a number of manufacturers as standard equipment for 1904, and Peerless made electrical headlamps standard in 1908. In 1912, Cadillac integrated their vehicle's Delco electrical ignition and lighting system, creating the modern vehicle electrical system.
Water flows into a bath through a 12 mm diameter pipe at a rate of 160 litre in 8 minutes. Find the flow velocity in the pipe, in m/s.
"Dipping" (low beam) headlamps were introduced in 1915 by the Guide Lamp Company, but the 1917 Cadillac system allowed the light to be dipped with a lever inside the car rather than requiring the driver to stop and get ...