What is the main purpose of the National Electrical Code? The NEC (the National Fire Protection Association’s NFPA 70) is a widely-adopted model code for the installation of electrical components and systems. Its purpose is to safeguard persons and property from hazards arising from the use of electricity (NEC 90.1(A)). What are the two basic […]
Is entropy positive or negative?
Is entropy positive or negative? Entropy, S, is a state function and is a measure of disorder or randomness. A positive (+) entropy change means an increase in disorder. The universe tends toward increased entropy. All spontaneous change occurs with an increase in entropy of the universe. Why is entropy generation always positive? A measure […]
What is the fastest plane in the world 2020?
What is the fastest plane in the world 2020? The Lockheed SR-71 Blackbird is the fastest jet aircraft in the world, reaching speeds of Mach 3.3–that’s more than 3,500 kph (2,100 mph) and almost four times as fast as the average cruising speed of a commercial airliner. Key elements of the SR-71’s design made this […]
Who was the first person to study psychology?
Who was the first person to study psychology? Wilhelm Wundt opened the Institute for Experimental Psychology at the University of Leipzig in Germany in 1879. This was the first laboratory dedicated to psychology, and its opening is usually thought of as the beginning of modern psychology. Indeed, Wundt is often regarded as the father of […]
What is momentum in physics definition?
What is momentum in physics definition? Momentum, product of the mass of a particle and its velocity. Momentum is a vector quantity; i.e., it has both magnitude and direction. Isaac Newton’s second law of motion states that the time rate of change of momentum is equal to the force acting on the particle. What is […]
What part of a plant leaves allows the plant to take in carbon dioxide and release oxygen?
What part of a plant leaves allows the plant to take in carbon dioxide and release oxygen? stomata What type of tissue do both plants and animals have? Organs are composed of tissues, which are in turn composed of cells. Plants have three tissue types: ground, dermal, and vascular. Animals have four: epithelial, connective, muscle, […]
How do I protect myself as a delivery driver?
How do I protect myself as a delivery driver? Lock your doors and go to the nearest safe location and/or call the police. Be alert to suspicious persons loitering around the delivery address. Don’t flash money during transactions. Make sure your car is in good working order. What is the most important element of driving? […]
What tool is used to measure the volume of an object?
Which state is not a physical state of matter?
Is an LED a passive component?
Is an LED a passive component? Some examples of active devices include solenoids, relays, LEDs, and microcontrollers or any other integrated chip that uses an external supply voltage (or current) to perform work or the intended function. LEDs are light emitting diodes, and we state above that diodes are considered passive. What are the different […]