Category: Physics

What is the difference between EMF and back EMF? The back emf is represented as a variable emf that opposes the emf driving the motor. Back emf is zero when the motor is not turning and increases proportionally to the motor’s angular velocity. The generator output of a motor is the difference between the supply […]

Which country has the best fuel? The International Fuel Quality Center (IFQC) has ranked the top 100 countries based on sulfur limits in gasoline; Germany was found to be at the top of the ranking with the lowest sulfur limits. Following in second and third were Japan and Sweden, respectively. What is the world largest […]

Does freezing water require energy? It takes 100 calories to heat 1 g. water from 0˚, the freezing point of water, to 100˚ C, the boiling point. However, 540 calories of energy are required to convert that 1 g of water at 100˚ C to 1 g of water vapor at 100˚ C. Does the […]

How many minutes a day should I exercise to lose weight? As a general goal, aim for at least 30 minutes of physical activity every day. If you want to lose weight, maintain weight loss or meet specific fitness goals, you may need to exercise more. What are the 7 healthful ways to lose weight? […]

What is the relationship between inductance and current? This induced voltage created by the changing current has the effect of opposing the change in current. This is stated by Lenz’s law, and the voltage is called back EMF. Inductance is defined as the ratio of the induced voltage to the rate of change of current […]

What is the strongest intermolecular forces in alcohols? Alcohols contain the hydroxyl group (O—H) which produce intermolecular forces of attraction through hydrogen bonding. Hydrogen bonds are much stronger than Van Der Waals’ intermolecular forces. Why are alcohols stronger than alkanes? Hydrogen bonding In alkanes, the only intermolecular forces are van der Waals dispersion forces. Hydrogen […]

Why shouldnt you walk on sand dunes? By walking or playing on sand dunes, we damage the beach grass and other plants that hold the dune together. It takes only a few footsteps to damage the extensive root system of beach grass, and when that happens, the plant can no longer hold sand in place. […]

How electric and magnetic fields are produced? Electric fields are produced by electric charges, and magnetic fields are produced by the flow of electrical current through wires or electrical devices. Because of this, low frequency EMR is found in close proximity to electrical sources such as power lines. What is the difference between electric fields […]

What are the 4 stages of voice production? It involves four processes: Initiation, phonation, oro-nasal process and articulation. Why does my voice sound like it’s vibrating? When you speak, air from your lungs is pushed between two elastic structures—called vocal folds—causing them to vibrate and produce your voice. In spasmodic dysphonia, the muscles inside the […]

What are Series sentences? A serial sentence is a sentence that contains a list of three or more words, phrases, clauses, etc. REMINDERS: In-Sentence Lists can be of any type of grammatical unit, such as nouns, verbs, participles, infinitives, or subordinate clauses. Is a series more than two? Series is both a singular and a […]