The iron needle sinks in water while the ship remains floating based on Archimedes' principle; option [B]. This principle states that the buoyant force exerted on an object immersed in a fluid is equal to the weight of the fluid displaced by the object. The ship's shape allows it to displace a volumRead more
The iron needle sinks in water while the ship remains floating based on Archimedes’ principle; option [B]. This principle states that the buoyant force exerted on an object immersed in a fluid is equal to the weight of the fluid displaced by the object. The ship’s shape allows it to displace a volume of water greater than its own weight, resulting in a net upward force that keeps it afloat. However, the density of iron is greater than that of water, causing the iron needle to displace less water than its own weight, resulting in a net downward force that causes it to sink. Therefore, it is Archimedes’ principle that explains why the ship floats while the iron needle sinks in water. Pascal’s principle relates to pressure in fluids, Kepler’s principle pertains to planetary motion, and the law of gravitation explains the attraction between masses.
The oil rises in the lamp wick due to capillary phenomenon; option [B]. The wick's fibers act as tiny tubes, creating capillary action. This action draws the oil upwards against gravity, allowing it to reach the flame, where it vaporizes and burns. This process sustains the lamp's flame by providingRead more
The oil rises in the lamp wick due to capillary phenomenon; option [B]. The wick’s fibers act as tiny tubes, creating capillary action. This action draws the oil upwards against gravity, allowing it to reach the flame, where it vaporizes and burns. This process sustains the lamp’s flame by providing a continuous supply of fuel.
While pressure difference and low viscosity of oil are factors influencing fluid movement, they are not the primary reasons for oil rising in the lamp wick. Similarly, the presence of carboxylic groups in the oil does not directly contribute to its capillary rise. Instead, it’s the capillary action resulting from the wick’s structure and the cohesive and adhesive forces between the oil and the wick fibers that enable the oil to travel upward, facilitating the lamp’s functionality.
When two capillaries of different diameters are immersed vertically in a liquid, the height of the rising liquid will be higher in the smaller diameter capillary; option [C]. This phenomenon is governed by the capillary action, which depends on the balance between cohesive forces within the liquid aRead more
When two capillaries of different diameters are immersed vertically in a liquid, the height of the rising liquid will be higher in the smaller diameter capillary; option [C]. This phenomenon is governed by the capillary action, which depends on the balance between cohesive forces within the liquid and adhesive forces between the liquid and the capillary walls. In narrower capillaries, the cohesive forces dominate, leading to greater rise of the liquid. Conversely, in wider capillaries, the adhesive forces are less effective in pulling the liquid upward, resulting in a lower rise. Therefore, the height of the rising liquid differs between capillaries of different diameters, with the smaller diameter capillary exhibiting a greater rise due to stronger capillary action. This principle is essential in various fields, including biology, chemistry, and materials science, where capillary phenomena play a significant role in processes such as fluid transport, plant biology, and surface science.
The unit of viscosity is Poise; option [A]. Viscosity is a measure of a fluid's resistance to flow, describing its internal friction. It is defined as the ratio of shear stress to shear rate within the fluid. The Poise is the standard unit used to quantify viscosity. It is named after French physiolRead more
The unit of viscosity is Poise; option [A]. Viscosity is a measure of a fluid’s resistance to flow, describing its internal friction. It is defined as the ratio of shear stress to shear rate within the fluid. The Poise is the standard unit used to quantify viscosity. It is named after French physiologist Jean Léonard Marie Poiseuille, who made significant contributions to the understanding of fluid dynamics and the study of viscosity. The Pascal, on the other hand, is a unit of pressure, while Poiseuille is a unit used to measure flow rate in fluid dynamics, particularly in the context of laminar flow through cylindrical tubes, named after Jean Léonard Marie Poiseuille. Therefore, the correct unit for viscosity is Poise, denoted by the symbol “P”.
If the diameter of the capillary is doubled, the height of the water surface rising in it remains the same; option [C]. This is governed by the capillary action phenomenon described by the Jurin's Law. According to this law, the height to which a liquid rises in a capillary tube is inversely proportRead more
If the diameter of the capillary is doubled, the height of the water surface rising in it remains the same; option [C]. This is governed by the capillary action phenomenon described by the Jurin’s Law. According to this law, the height to which a liquid rises in a capillary tube is inversely proportional to the diameter of the tube. Therefore, doubling the diameter would result in halving the height, and vice versa. However, if the diameter is doubled, the effect cancels out, and the height remains unchanged. This principle is essential in various fields such as fluid mechanics, biology, and materials science, where capillary action plays a crucial role in phenomena like plant water uptake, ink absorption in paper, and the functioning of microfluidic devices. Understanding this relationship between capillary diameter and height helps in designing and optimizing systems utilizing capillary action for various applications.
Astronauts cannot stand straight in space because there is no gravity; option [A]. In the microgravity environment of space, there is no significant gravitational force pulling them towards any particular direction. As a result, they experience weightlessness and float freely, unable to stand in theRead more
Astronauts cannot stand straight in space because there is no gravity; option [A]. In the microgravity environment of space, there is no significant gravitational force pulling them towards any particular direction. As a result, they experience weightlessness and float freely, unable to stand in the traditional sense. Instead, they rely on restraints and handholds to stabilize themselves and move around in spacecraft or space stations. While other forces, such as the solar wind or atmospheric pressure, may affect space missions in various ways, they do not directly influence the ability of astronauts to stand straight in space. It is the absence of gravity that fundamentally alters the behavior of objects and individuals in the space environment, requiring astronauts to adapt and use specialized equipment for mobility and stability.
Ventilators are installed near the ceiling of the room primarily because the exhaled hot air rises up and goes out; option [A]. Hot air is less dense than cold air, causing it to ascend towards the ceiling. By placing ventilators near the ceiling, they effectively expel this hot air, promoting betteRead more
Ventilators are installed near the ceiling of the room primarily because the exhaled hot air rises up and goes out; option [A]. Hot air is less dense than cold air, causing it to ascend towards the ceiling. By placing ventilators near the ceiling, they effectively expel this hot air, promoting better air circulation and ventilation within the room.
Additionally, installing ventilators near the ceiling helps to provide cross ventilation in the room. Cross ventilation involves the flow of air through opposing openings, such as windows or ventilators, allowing fresh air to enter while stale air exits. Placing ventilators strategically near the ceiling enables them to work in conjunction with other openings in the room, facilitating the exchange of air and maintaining indoor air quality.
Moreover, ventilators near the ceiling do not necessarily provide light to the room. Their primary function is ventilation, not illumination. Lighting fixtures or windows are typically used to provide illumination in a room, while ventilators focus on improving air quality and comfort.
As for aesthetics, the placement of ventilators near the ceiling is more practical than decorative. While aesthetics may play a role in design considerations, the primary reason for installing ventilators near the ceiling is to optimize air circulation and ventilation within the room.
When soap is dissolved in water, the surface tension initially decreases; option [A]. Soap molecules contain hydrophilic heads and hydrophobic tails. The hydrophobic tails disrupt the cohesive forces between water molecules at the surface, reducing surface tension. This decrease facilitates the spreRead more
When soap is dissolved in water, the surface tension initially decreases; option [A]. Soap molecules contain hydrophilic heads and hydrophobic tails. The hydrophobic tails disrupt the cohesive forces between water molecules at the surface, reducing surface tension. This decrease facilitates the spreading of water and enhances its ability to wet surfaces, enabling effective cleaning.
However, at higher concentrations of soap, the excess molecules can aggregate to form structures called micelles. In these micelles, the hydrophobic tails are shielded from the water, leading to a slight increase in surface tension compared to the initial decrease. This increase occurs because the micelles effectively reduce the number of free soap molecules available to disrupt the water’s surface tension directly.
Therefore, the behavior of surface tension when soap is dissolved in water can be described as initially decreasing due to the disruptive action of individual soap molecules, followed by a potential slight increase as micelles form at higher concentrations. Overall, the presence of soap alters the surface tension of water, impacting its properties and enhancing its effectiveness in cleaning applications.
When detergent is added to pure water, the surface tension decreases; option [B]. Detergent molecules contain both hydrophilic and hydrophobic components. The hydrophilic part interacts with water molecules, while the hydrophobic part disrupts the cohesive forces between water molecules at the surfaRead more
When detergent is added to pure water, the surface tension decreases; option [B]. Detergent molecules contain both hydrophilic and hydrophobic components. The hydrophilic part interacts with water molecules, while the hydrophobic part disrupts the cohesive forces between water molecules at the surface. As a result, the surface tension of the water decreases, allowing the detergent solution to spread more easily over surfaces and penetrate materials for effective cleaning. This reduction in surface tension enhances the detergent’s ability to wet surfaces and lift away dirt and grease. Consequently, adding detergent to water improves its cleaning properties compared to pure water alone. This phenomenon is widely utilized in various applications, from household cleaning to industrial processes, where reducing surface tension is essential for achieving thorough and efficient cleaning results.
Small pieces of camphor dance on the surface of water primarily due to surface tension; option [A]. When camphor is placed on water, it quickly sublimes, transitioning from a solid to a gas phase. This sublimation releases camphor molecules into the surrounding air. As these molecules diffuse outwarRead more
Small pieces of camphor dance on the surface of water primarily due to surface tension; option [A]. When camphor is placed on water, it quickly sublimes, transitioning from a solid to a gas phase. This sublimation releases camphor molecules into the surrounding air. As these molecules diffuse outward, they create a localized concentration gradient at the water’s surface.
Surface tension, a property of liquids arising from cohesive forces between molecules, causes the water’s surface to behave like a thin elastic film. When the camphor molecules diffuse to the water’s surface, they disrupt this surface tension, creating regions of lower surface tension around them.
Consequently, the surface tension exerts a force on the camphor pieces, causing them to move in a direction away from the region of higher surface tension. This movement is akin to a boat propelled by the release of air bubbles underwater. As a result, the camphor pieces appear to “dance” or move chaotically on the water’s surface.
While camphor does have certain properties that contribute to its behavior on water, such as its low solubility and volatility, it is primarily the interaction between camphor molecules and the surface tension of water that causes the dancing motion.
An iron needle sinks in water but the ship remains floating. On what principle is it based?
The iron needle sinks in water while the ship remains floating based on Archimedes' principle; option [B]. This principle states that the buoyant force exerted on an object immersed in a fluid is equal to the weight of the fluid displaced by the object. The ship's shape allows it to displace a volumRead more
The iron needle sinks in water while the ship remains floating based on Archimedes’ principle; option [B]. This principle states that the buoyant force exerted on an object immersed in a fluid is equal to the weight of the fluid displaced by the object. The ship’s shape allows it to displace a volume of water greater than its own weight, resulting in a net upward force that keeps it afloat. However, the density of iron is greater than that of water, causing the iron needle to displace less water than its own weight, resulting in a net downward force that causes it to sink. Therefore, it is Archimedes’ principle that explains why the ship floats while the iron needle sinks in water. Pascal’s principle relates to pressure in fluids, Kepler’s principle pertains to planetary motion, and the law of gravitation explains the attraction between masses.
See lessWhat causes the oil to rise in the lamp wick?
The oil rises in the lamp wick due to capillary phenomenon; option [B]. The wick's fibers act as tiny tubes, creating capillary action. This action draws the oil upwards against gravity, allowing it to reach the flame, where it vaporizes and burns. This process sustains the lamp's flame by providingRead more
The oil rises in the lamp wick due to capillary phenomenon; option [B]. The wick’s fibers act as tiny tubes, creating capillary action. This action draws the oil upwards against gravity, allowing it to reach the flame, where it vaporizes and burns. This process sustains the lamp’s flame by providing a continuous supply of fuel.
While pressure difference and low viscosity of oil are factors influencing fluid movement, they are not the primary reasons for oil rising in the lamp wick. Similarly, the presence of carboxylic groups in the oil does not directly contribute to its capillary rise. Instead, it’s the capillary action resulting from the wick’s structure and the cohesive and adhesive forces between the oil and the wick fibers that enable the oil to travel upward, facilitating the lamp’s functionality.
See lessWhen two capillaries of different diameters are immersed vertically in a liquid, the height of the rising liquid
When two capillaries of different diameters are immersed vertically in a liquid, the height of the rising liquid will be higher in the smaller diameter capillary; option [C]. This phenomenon is governed by the capillary action, which depends on the balance between cohesive forces within the liquid aRead more
When two capillaries of different diameters are immersed vertically in a liquid, the height of the rising liquid will be higher in the smaller diameter capillary; option [C]. This phenomenon is governed by the capillary action, which depends on the balance between cohesive forces within the liquid and adhesive forces between the liquid and the capillary walls. In narrower capillaries, the cohesive forces dominate, leading to greater rise of the liquid. Conversely, in wider capillaries, the adhesive forces are less effective in pulling the liquid upward, resulting in a lower rise. Therefore, the height of the rising liquid differs between capillaries of different diameters, with the smaller diameter capillary exhibiting a greater rise due to stronger capillary action. This principle is essential in various fields, including biology, chemistry, and materials science, where capillary phenomena play a significant role in processes such as fluid transport, plant biology, and surface science.
See lessThe unit of viscosity is
The unit of viscosity is Poise; option [A]. Viscosity is a measure of a fluid's resistance to flow, describing its internal friction. It is defined as the ratio of shear stress to shear rate within the fluid. The Poise is the standard unit used to quantify viscosity. It is named after French physiolRead more
The unit of viscosity is Poise; option [A]. Viscosity is a measure of a fluid’s resistance to flow, describing its internal friction. It is defined as the ratio of shear stress to shear rate within the fluid. The Poise is the standard unit used to quantify viscosity. It is named after French physiologist Jean Léonard Marie Poiseuille, who made significant contributions to the understanding of fluid dynamics and the study of viscosity. The Pascal, on the other hand, is a unit of pressure, while Poiseuille is a unit used to measure flow rate in fluid dynamics, particularly in the context of laminar flow through cylindrical tubes, named after Jean Léonard Marie Poiseuille. Therefore, the correct unit for viscosity is Poise, denoted by the symbol “P”.
See lessIf the diameter of the capillary is doubled then the height of the water surface rising in it
If the diameter of the capillary is doubled, the height of the water surface rising in it remains the same; option [C]. This is governed by the capillary action phenomenon described by the Jurin's Law. According to this law, the height to which a liquid rises in a capillary tube is inversely proportRead more
If the diameter of the capillary is doubled, the height of the water surface rising in it remains the same; option [C]. This is governed by the capillary action phenomenon described by the Jurin’s Law. According to this law, the height to which a liquid rises in a capillary tube is inversely proportional to the diameter of the tube. Therefore, doubling the diameter would result in halving the height, and vice versa. However, if the diameter is doubled, the effect cancels out, and the height remains unchanged. This principle is essential in various fields such as fluid mechanics, biology, and materials science, where capillary action plays a crucial role in phenomena like plant water uptake, ink absorption in paper, and the functioning of microfluidic devices. Understanding this relationship between capillary diameter and height helps in designing and optimizing systems utilizing capillary action for various applications.
See lessAstronauts cannot stand straight in space because
Astronauts cannot stand straight in space because there is no gravity; option [A]. In the microgravity environment of space, there is no significant gravitational force pulling them towards any particular direction. As a result, they experience weightlessness and float freely, unable to stand in theRead more
Astronauts cannot stand straight in space because there is no gravity; option [A]. In the microgravity environment of space, there is no significant gravitational force pulling them towards any particular direction. As a result, they experience weightlessness and float freely, unable to stand in the traditional sense. Instead, they rely on restraints and handholds to stabilize themselves and move around in spacecraft or space stations. While other forces, such as the solar wind or atmospheric pressure, may affect space missions in various ways, they do not directly influence the ability of astronauts to stand straight in space. It is the absence of gravity that fundamentally alters the behavior of objects and individuals in the space environment, requiring astronauts to adapt and use specialized equipment for mobility and stability.
See lessVentilators are installed near the ceiling of the room, because
Ventilators are installed near the ceiling of the room primarily because the exhaled hot air rises up and goes out; option [A]. Hot air is less dense than cold air, causing it to ascend towards the ceiling. By placing ventilators near the ceiling, they effectively expel this hot air, promoting betteRead more
Ventilators are installed near the ceiling of the room primarily because the exhaled hot air rises up and goes out; option [A]. Hot air is less dense than cold air, causing it to ascend towards the ceiling. By placing ventilators near the ceiling, they effectively expel this hot air, promoting better air circulation and ventilation within the room.
Additionally, installing ventilators near the ceiling helps to provide cross ventilation in the room. Cross ventilation involves the flow of air through opposing openings, such as windows or ventilators, allowing fresh air to enter while stale air exits. Placing ventilators strategically near the ceiling enables them to work in conjunction with other openings in the room, facilitating the exchange of air and maintaining indoor air quality.
Moreover, ventilators near the ceiling do not necessarily provide light to the room. Their primary function is ventilation, not illumination. Lighting fixtures or windows are typically used to provide illumination in a room, while ventilators focus on improving air quality and comfort.
As for aesthetics, the placement of ventilators near the ceiling is more practical than decorative. While aesthetics may play a role in design considerations, the primary reason for installing ventilators near the ceiling is to optimize air circulation and ventilation within the room.
See lessWhen soap is dissolved in water, the surface tension
When soap is dissolved in water, the surface tension initially decreases; option [A]. Soap molecules contain hydrophilic heads and hydrophobic tails. The hydrophobic tails disrupt the cohesive forces between water molecules at the surface, reducing surface tension. This decrease facilitates the spreRead more
When soap is dissolved in water, the surface tension initially decreases; option [A]. Soap molecules contain hydrophilic heads and hydrophobic tails. The hydrophobic tails disrupt the cohesive forces between water molecules at the surface, reducing surface tension. This decrease facilitates the spreading of water and enhances its ability to wet surfaces, enabling effective cleaning.
However, at higher concentrations of soap, the excess molecules can aggregate to form structures called micelles. In these micelles, the hydrophobic tails are shielded from the water, leading to a slight increase in surface tension compared to the initial decrease. This increase occurs because the micelles effectively reduce the number of free soap molecules available to disrupt the water’s surface tension directly.
Therefore, the behavior of surface tension when soap is dissolved in water can be described as initially decreasing due to the disruptive action of individual soap molecules, followed by a potential slight increase as micelles form at higher concentrations. Overall, the presence of soap alters the surface tension of water, impacting its properties and enhancing its effectiveness in cleaning applications.
See lessWhen detergent is added to pure water, the surface tension
When detergent is added to pure water, the surface tension decreases; option [B]. Detergent molecules contain both hydrophilic and hydrophobic components. The hydrophilic part interacts with water molecules, while the hydrophobic part disrupts the cohesive forces between water molecules at the surfaRead more
When detergent is added to pure water, the surface tension decreases; option [B]. Detergent molecules contain both hydrophilic and hydrophobic components. The hydrophilic part interacts with water molecules, while the hydrophobic part disrupts the cohesive forces between water molecules at the surface. As a result, the surface tension of the water decreases, allowing the detergent solution to spread more easily over surfaces and penetrate materials for effective cleaning. This reduction in surface tension enhances the detergent’s ability to wet surfaces and lift away dirt and grease. Consequently, adding detergent to water improves its cleaning properties compared to pure water alone. This phenomenon is widely utilized in various applications, from household cleaning to industrial processes, where reducing surface tension is essential for achieving thorough and efficient cleaning results.
See lessWhy do small pieces of camphor dance on the surface of water?
Small pieces of camphor dance on the surface of water primarily due to surface tension; option [A]. When camphor is placed on water, it quickly sublimes, transitioning from a solid to a gas phase. This sublimation releases camphor molecules into the surrounding air. As these molecules diffuse outwarRead more
Small pieces of camphor dance on the surface of water primarily due to surface tension; option [A]. When camphor is placed on water, it quickly sublimes, transitioning from a solid to a gas phase. This sublimation releases camphor molecules into the surrounding air. As these molecules diffuse outward, they create a localized concentration gradient at the water’s surface.
See lessSurface tension, a property of liquids arising from cohesive forces between molecules, causes the water’s surface to behave like a thin elastic film. When the camphor molecules diffuse to the water’s surface, they disrupt this surface tension, creating regions of lower surface tension around them.
Consequently, the surface tension exerts a force on the camphor pieces, causing them to move in a direction away from the region of higher surface tension. This movement is akin to a boat propelled by the release of air bubbles underwater. As a result, the camphor pieces appear to “dance” or move chaotically on the water’s surface.
While camphor does have certain properties that contribute to its behavior on water, such as its low solubility and volatility, it is primarily the interaction between camphor molecules and the surface tension of water that causes the dancing motion.