Summary of Empuje-Tensión Superficial (semana 9-Pre San Marcos)-Hidrostática

00:00:00 - 00:15:00

In this section of the video, the YouTuber explains the concept of empuje, which refers to the upward force experienced by a submerged object. The empuje is calculated using the formula: empuje = densidad del líquido x gravedad x volumen sumergido, and the YouTuber provides examples of how to use this formula to represent the empuje in a diagram. The YouTuber then goes on to discuss the principle of buoyancy, which is the upward force experienced by an object partially submerged in a liquid. This force is equal to the weight of the liquid displaced by the object. The YouTuber also introduces the formula for calculating buoyant force, which involves the density of the liquid, acceleration due to gravity, and the volume of the object submerged. The YouTuber discusses the concept of apparent weight and how it changes when an object is submerged in a liquid. He emphasizes that surface tension and capillarity occur in liquids, and he provides formulas to calculate the height of a liquid in a capillary tube.

• 00:00:00 In this section, the YouTuber explains the concept of empuje hidrostático, which is the force pushing a submerged object upwards when it is partially or completely submerged in a liquid. The empuje is caused by the liquid surrounding the object exerting a force on it, which can be calculated using the formula: empuje = densidad del líquido x gravedad x volumen sumergido. The YouTuber then moves on to explaining the second part of the topic, which involves the principle of archaemedes, which states that any object placed in a liquid experiences an upward force equal to the weight of the liquid displaced by the object. The YouTuber provides an example of how to calculate the force of empuje using the formula and explains the different ways to represent the empuje in a diagram, which can either be a rectangle or a circle. The YouTuber then explains the institution of Archimedes and how the principle of theirs refers to buoyancy, which is the upward force directed upwards when an object is partially submerged in a liquid.
• 00:05:00 In this section, the speaker uses a diagram to explain the concept of buoyant force and the principle of Archimedes. The speaker demonstrates how a body submerged in a liquid experiences an upward force called buoyant force or "empuje." According to the principle of Archimedes, this buoyant force is equal to the weight of the liquid displaced by the submerged body. The speaker also introduces a formula to calculate buoyant force, which involves the density of the liquid, acceleration due to gravity, and the volume of the object submerged. Additionally, the speaker discusses the concept of apparent weight and how it changes when an object is submerged in a liquid. The speaker poses a question about whether it is easier to lift a 5-kilogram sphere in the air or in water, highlighting the difference in apparent weight in the two scenarios.
• 00:10:00 In this section, the instructor explains the concept of apparent weight and buoyant force in a liquid. He emphasizes that when an object is submerged in a liquid, it appears to weigh less due to the upward buoyant force exerted by the liquid. He introduces the formula for apparent weight, which is equal to the actual weight of the object minus the buoyant force. He also discusses the concept of surface tension, which is the phenomenon that allows lightweight objects to float on the surface of a liquid. He mentions that surface tension is inversely proportional to temperature, meaning that as the temperature of a liquid increases, its surface tension decreases. Lastly, he explains the capillarity phenomenon, where liquids can rise or sink in thin tubes due to surface tension. He provides a formula to calculate the height to which a liquid can rise in a capillary tube.
• 00:15:00 In this section, the professor explains the concept of surface tension mathematically, which is defined as the force per unit length. This force is measured in Newtons per meter, as both force and length are measured in these units. The professor also explains that the coseno of an angle (θ) must be considered in this situation, where the force is applied to the walls of a tube or similar structures, and the θ value is given in the formula. The professor advises that students should not worry about this detail and focus on the data provided. The professor then discusses the density (ρ) of the liquid being used. The acceleration of gravity (g) and the capillary radius (r) are also mentioned. The base of the tubing used is circular and has a diameter of 5 centimeters. The radius of the base of the tube is 1 centimeter, which is provided for students. The professor advises students to remember that the radius is simply half of the diameter, and the unit of measurement for both is in meters. The professor then emphasizes that failure is not an option and encourages students to persevere and not give up until the last exam. He advises students to make a small prayer before their exams, which can bring peace and help them succeed.