Who was arrested for refusing to give up a seat on the bus and why is this significant? The boycott took place from December 5, 1955, to December 20, 1956, and is regarded as the first large-scale U.S. demonstration against segregation. Four days before the boycott began, Rosa Parks, an African American woman, was arrested […]
What happens in the circuit when the switch is moved from the off position to the on position?
What happens in the circuit when the switch is moved from the off position to the on position? When a switch is in the ‘on’ position it allows the electricity flow to enter the main electrical circuit and the circuit becomes a closed circuit. On the other hand,when a switch is in the ‘off’ position […]
Who uses psychrometric chart?
Who uses psychrometric chart? Psychrometric charts are complex graphs that can be used to assess the physical and thermodynamic properties of gas-vapour mixtures at a constant pressure. They are often used to assess the properties of moist air. What is psychrometric chart in HVAC? Psychrometric chart is one of the chart that is commonly used […]
What did the oil drop experiment determine?
What did the oil drop experiment determine? In 1909, Robert Millikan and Harvey Fletcher conducted the oil drop experiment to determine the charge of an electron. They suspended tiny charged droplets of oil between two metal electrodes by balancing downward gravitational force with upward drag and electric forces. Why was the oil drop experiment important? […]
How does an ocean thermal energy conversion OTEC system work?
How does an ocean thermal energy conversion OTEC system work? Ocean Thermal Energy Conversion (OTEC) systems use a temperature difference (of at least 77° Fahrenheit) to power a turbine to produce electricity. The vaporized fluid drives a turbine/generator. The vaporized fluid is turned back to a liquid in a condenser cooled with cold ocean water […]
What is the working principle of microwave oven?
What is the working principle of microwave oven? A microwave oven uses microwaves, which are basically radio waves, to cook food. The commonly used frequency is roughly 2,500 MHz (2.5 GHz). Radio waves in this frequency range are absorbed by water, fats and sugars. When absorbed, they are converted directly into heat. What is the […]
What information is displayed on the capacity plate of an outboard powerboat?
What information is displayed on the capacity plate of an outboard powerboat? What information is displayed on the capacity plate of an outboard powerboat? the maximum weight and number of people that the boat can carry and horsepower rating. What does a boat less than 20 feet must have? Federal law mandates that boats of […]
Why is a compact fluorescent light bulb more efficient than an incandescent bulb?
Why is a compact fluorescent light bulb more efficient than an incandescent bulb? The phosphor fluoresces to produce light. A fluorescent bulb produces less heat, so it is much more efficient. A fluorescent bulb can produce between 50 and 100 lumens per watt. This makes fluorescent bulbs four to six times more efficient than incandescent […]
How are folding doors used?
How are folding doors used? Folding doors can be used as internal or external room dividers and are made from a variety of materials. Most folding doors are glazed and the panels have frames of either wood, aluminium or upvc. They can open up and fold either internally or externally and are widely used in […]
What is the difference between single ended and differential signaling?
What is the difference between single ended and differential signaling? Single-ended inputs are lower in cost, and provide twice the number of inputs for the same size wiring connector, since they require only one analog HIGH (+) input per channel and one LLGND (-) shared by all inputs. Differential signals require signal HIGH and LOW […]