How can entropy be reduced? When a small amount of heat ΔQ is added to a substance at temperature T, without changing its temperature appreciably, the entropy of the substance changes by ΔS = ΔQ/T. When heat is removed, the entropy decreases, when heat is added the entropy increases. Entropy has units of Joules per […]
What is the output frequency for a frequency division circuit that contains 12 flip flops with an input clock frequency of 20.48 MHz?
What is the output frequency for a frequency division circuit that contains 12 flip flops with an input clock frequency of 20.48 MHz? 12. Determine the output frequency for a frequency division circuit that contains 12 flip-flops with an input clock frequency of 20.48 MHz. Output Clock frequency = = 5000 i.e., 5 kHz. How […]
What kind of piping is used in an ammonia refrigeration system?
What kind of piping is used in an ammonia refrigeration system? Steel piping What is refrigeration copper tubing? Copper, used for refrigeration, is designated as ACR copper. Measure the inside and outside diameter of the end of the tube. The outside diameter of Type L is always 1/8-inch larger than the size marked on the […]
What is the input impedance of a common emitter amplifier?
What is the input impedance of a common emitter amplifier? around 1kΩ How do you test for impedance? To find the output impedance the output voltage is measured first with no load resistor, then with a fixed load (purely resistive). To measure the input impedance over a complete spectrum of frequencies, use the following circuit: […]
What are the different mechanisms for diffusion?
What are the different mechanisms for diffusion? Diffusion can occur by two different mechanisms: interstitial diffusion and substitutional diffusion. Picture an impurity atom in an otherwise perfect structure. Which diffusion mechanism is faster interstitial or vacancy? Interstitial diffusion is generally faster than vacancy diffusion because bonding of interstitials to the surrounding atoms is normally weaker […]
How do you find the maximum theoretical efficiency?
How do you find the maximum theoretical efficiency? The maximum theoretical efficiency of a heat engine (which no engine ever attains) is equal to the temperature difference between the hot and cold ends divided by the temperature at the hot end, each expressed in absolute temperature (Kelvin). What is the theoretical maximum efficiency? The Carnot […]
What type of current is used in arc welding?
What type of current is used in arc welding? Both direct current (D.C.) and alternating current (A.C.) are used for arc welding. The alternating current for arc is obtained from a step down transformer. The transformer receives current from the main supply at 220 to 440 volts and step down to required voltage i.e., 80 […]
Which of the following is suitable for job shop production?
Which of the following is suitable for job shop production? General purpose machines are suitable in job shops because they are capable of performing many different types of operations and thus capable of producing a wide variety of products with small lot sizes. Machines which perform similar function grouped together. What is meant by job […]
Why is organic farming better?
Why is organic farming better? Organic farming tends to be better for the environment. Organic farming practices may reduce pollution, conserve water, reduce soil erosion, increase soil fertility, and use less energy. Farming without synthetic pesticides is also better for nearby birds and animals as well as people who live close to farms. Are organic […]
How is metabolism important in nutrition processes?
How is metabolism important in nutrition processes? Nutrition is the key to metabolism. The pathways of metabolism rely upon nutrients that they breakdown in order to produce energy. This energy in turn is required by the body to synthesize molecules like new proteins and nucleic acids (DNA, RNA). How is metabolism regulated in the body? […]