A person at rest in the middle of a horizontal plane of perfectly smooth ice can bring themselves to the shore by utilizing the first law of motion, also known as the law of inertia; option [A]. This law states that an object at rest will remain at rest unless acted upon by an external force. In thiRead more
A person at rest in the middle of a horizontal plane of perfectly smooth ice can bring themselves to the shore by utilizing the first law of motion, also known as the law of inertia; option [A]. This law states that an object at rest will remain at rest unless acted upon by an external force. In this scenario, the person can initiate motion towards the shore by exerting a force against the ice in the opposite direction. By pushing against the ice with their feet or by using some other means, the person applies a force that overcomes the inertia of their own body, causing them to move towards the shore.
While the second law of motion relates force, mass, and acceleration, and the third law of motion describes action and reaction forces, these laws are not directly applicable in this context. The first law, however, specifically addresses the tendency of objects to remain at rest or in uniform motion unless acted upon by an external force, making it the relevant principle for the person’s movement on the smooth ice.
When the child throws the ball straight up in the air while inside a car moving at a constant speed, the motion of the ball is influenced by both the initial velocity imparted by the child and the uniform motion of the car. Since the car is moving with a constant velocity, there are no additional foRead more
When the child throws the ball straight up in the air while inside a car moving at a constant speed, the motion of the ball is influenced by both the initial velocity imparted by the child and the uniform motion of the car. Since the car is moving with a constant velocity, there are no additional forces acting on the ball while it is in the air relative to the car. Therefore, the ball follows a simple parabolic trajectory, going vertically upwards due to the initial throw and then falling downwards, relative to the car’s frame of reference; option [C].
Since the ball has no horizontal motion relative to the car, it remains directly above the child throughout its flight. As a result, when it descends, it falls back into the hands of the child, assuming the child’s hands remain in the same position throughout the motion. This is because both the child and the ball are moving at the same velocity horizontally, so there’s no relative motion between them in the horizontal direction. Consequently, the correct option is [C] in his hand, as the ball returns to the child’s hand due to the absence of any external horizontal forces acting on it within the car’s frame of reference.
The hairs of the shaving brush stick together when taken out of water primarily due to surface tension; option [A]. Surface tension arises from cohesive forces between water molecules, causing them to attract each other. When the shaving brush is submerged in water, water molecules adhere to the haiRead more
The hairs of the shaving brush stick together when taken out of water primarily due to surface tension; option [A]. Surface tension arises from cohesive forces between water molecules, causing them to attract each other. When the shaving brush is submerged in water, water molecules adhere to the hairs and create a thin film on their surface. Upon removal from water, the cohesive forces between the water molecules cause them to cling together, resulting in the hairs sticking together.
While viscosity, elasticity, and friction play roles in various phenomena, they are not the primary reasons for the hairs of the shaving brush sticking together. Viscosity refers to a fluid’s resistance to flow and does not directly affect the hairs of the brush. Elasticity pertains to the ability of a material to return to its original shape after deformation and is not relevant to the sticking of the hairs. Friction is the resistance encountered when one object slides over another, but it is not the dominant factor in this scenario.
Understanding the role of surface tension elucidates why the hairs of the shaving brush tend to stick together when removed from water, a phenomenon commonly observed in daily grooming routines.
When kerosene oil is added to stagnant water, mosquitoes reduce because it interferes with the breathing of the larvae; option [C]. Kerosene forms a thin film on the water's surface, which blocks the larvae's access to air. Since mosquito larvae need to breathe air through a siphon at the water surfRead more
When kerosene oil is added to stagnant water, mosquitoes reduce because it interferes with the breathing of the larvae; option [C]. Kerosene forms a thin film on the water’s surface, which blocks the larvae’s access to air. Since mosquito larvae need to breathe air through a siphon at the water surface, the layer of kerosene prevents them from doing so effectively, leading to suffocation and mortality. This disruption of their respiratory process significantly impairs their ability to survive and develop into adult mosquitoes.
While kerosene does not directly poison the mosquitoes or drive them away, its presence alters the environment in a way that is inhospitable to mosquito larvae. By obstructing their access to essential air, kerosene effectively hinders their development and reproduction cycle. This method is often used as a non-toxic approach to mosquito control, as it targets the larvae rather than adult mosquitoes. Consequently, by reducing the mosquito population at the larval stage, it helps mitigate the risk of mosquito-borne diseases and discomfort caused by adult mosquitoes.
The shape of a raindrop becomes spherical primarily due to surface tension; option [B]. Surface tension is the cohesive force between water molecules at the surface, causing them to pull inward. When a raindrop forms, surface tension acts equally in all directions, minimizing the surface area and puRead more
The shape of a raindrop becomes spherical primarily due to surface tension; option [B]. Surface tension is the cohesive force between water molecules at the surface, causing them to pull inward. When a raindrop forms, surface tension acts equally in all directions, minimizing the surface area and pulling the drop into a spherical shape. This occurs despite the influence of gravity, which tends to deform the drop slightly. While viscosity, elasticity, and gravity play roles in the behavior of raindrops, surface tension is the dominant force determining their shape. Raindrops maintain their spherical form until they encounter air resistance or other forces that may cause deformation. Understanding the interplay between surface tension and external forces helps explain the characteristic shape of raindrops and their behavior during precipitation events.
The principle of purification by soap is based on surface tension; option [A]. Soap molecules contain both hydrophilic and hydrophobic parts. When soap is added to water, its hydrophobic tails attach to oil and grease, while the hydrophilic heads face outward. This forms structures called micelles,Read more
The principle of purification by soap is based on surface tension; option [A]. Soap molecules contain both hydrophilic and hydrophobic parts. When soap is added to water, its hydrophobic tails attach to oil and grease, while the hydrophilic heads face outward. This forms structures called micelles, which encapsulate the dirt and oil, breaking them into smaller droplets suspended in the water. These micelles reduce the surface tension of water, allowing the trapped particles to be easily lifted away. This mechanism is essential for cleaning surfaces as it prevents the redeposition of dirt and oil onto cleaned surfaces. Therefore, the effectiveness of soap in purification is fundamentally tied to its ability to alter surface tension, facilitating the removal of contaminants and ensuring thorough cleaning across various surfaces.
Oil spreads on the surface of water primarily due to differences in surface tension between the two substances. The surface tension of water is higher than that of oil. This means that water molecules tend to stick together more strongly at the surface, forming a "skin" that resists penetration. InRead more
Oil spreads on the surface of water primarily due to differences in surface tension between the two substances. The surface tension of water is higher than that of oil. This means that water molecules tend to stick together more strongly at the surface, forming a “skin” that resists penetration. In contrast, oil molecules have weaker intermolecular forces at the surface, allowing them to spread out more easily. This phenomenon occurs despite the fact that oil is less dense than water; option [D]. Oil molecules move to the water’s surface to minimize contact with water molecules, creating a thin layer. This behavior is essential in environmental contexts, such as oil spills, where oil can spread rapidly over large areas of water. Understanding the surface tension properties of oil and water is crucial for managing and mitigating the environmental impacts of such incidents.
H5N1 bird flu is a subtype of influenza A virus that primarily infects birds but can also be transmitted to humans. It poses a significant threat to both animal and human health. In birds, H5N1 can cause severe illness and high mortality rates, leading to significant economic losses in the poultry iRead more
H5N1 bird flu is a subtype of influenza A virus that primarily infects birds but can also be transmitted to humans. It poses a significant threat to both animal and human health. In birds, H5N1 can cause severe illness and high mortality rates, leading to significant economic losses in the poultry industry. When humans are infected, typically through direct contact with infected birds or contaminated environments, H5N1 can result in severe respiratory illness and, in some cases, death. While human-to-human transmission of H5N1 is rare, it has the potential to lead to a widespread outbreak or pandemic if the virus undergoes genetic changes that allow for efficient transmission between people. Monitoring and control measures, including surveillance, vaccination, and biosecurity protocols, are essential for preventing and managing outbreaks of H5N1 bird flu.
Australia is the continent with a complete absence of volcanoes. Unlike other continents, such as Asia, Europe, and even Antarctica, which have witnessed volcanic activity, Australia lacks any active volcanic systems. This absence can be attributed to Australia's position on the tectonic plates. WhiRead more
Australia is the continent with a complete absence of volcanoes. Unlike other continents, such as Asia, Europe, and even Antarctica, which have witnessed volcanic activity, Australia lacks any active volcanic systems. This absence can be attributed to Australia’s position on the tectonic plates. While Australia has experienced volcanic activity in the distant past, particularly during the Paleozoic and Mesozoic eras, it has since become geologically stable. The continent is situated within the interior of the Indo-Australian Plate, far away from any active plate boundaries where volcanic activity typically occurs. Consequently, Australia is characterized by a lack of recent volcanic features such as volcanic peaks, lava fields, or volcanic activity, making it unique among the continents in terms of its geological profile.
The Tropics of Cancer, Equator, and Capricorn intersect with the continent of Africa, positioning it uniquely within the global geographical framework. The Equator, an imaginary line dividing the Earth into northern and southern hemispheres, traverses through central Africa, bestowing equatorial cliRead more
The Tropics of Cancer, Equator, and Capricorn intersect with the continent of Africa, positioning it uniquely within the global geographical framework. The Equator, an imaginary line dividing the Earth into northern and southern hemispheres, traverses through central Africa, bestowing equatorial climates upon countries like the Democratic Republic of Congo and Uganda. Further north, the Tropic of Cancer cuts through northern Africa, influencing the climates of countries such as Egypt and Libya. Conversely, the Tropic of Capricorn crosses the southern part of Africa, affecting climates in nations like Namibia and Botswana. This convergence of significant latitudinal lines contributes to Africa’s diverse climate zones, ranging from tropical rainforests near the Equator to arid deserts near the Tropics, showcasing the continent’s rich geographical diversity and its profound impact on the region’s ecosystems, cultures, and societies.
A person is at rest in the middle of a horizontal plane of perfectly smooth ice. By using which law of Newton can he bring himself to the shore?
A person at rest in the middle of a horizontal plane of perfectly smooth ice can bring themselves to the shore by utilizing the first law of motion, also known as the law of inertia; option [A]. This law states that an object at rest will remain at rest unless acted upon by an external force. In thiRead more
A person at rest in the middle of a horizontal plane of perfectly smooth ice can bring themselves to the shore by utilizing the first law of motion, also known as the law of inertia; option [A]. This law states that an object at rest will remain at rest unless acted upon by an external force. In this scenario, the person can initiate motion towards the shore by exerting a force against the ice in the opposite direction. By pushing against the ice with their feet or by using some other means, the person applies a force that overcomes the inertia of their own body, causing them to move towards the shore.
While the second law of motion relates force, mass, and acceleration, and the third law of motion describes action and reaction forces, these laws are not directly applicable in this context. The first law, however, specifically addresses the tendency of objects to remain at rest or in uniform motion unless acted upon by an external force, making it the relevant principle for the person’s movement on the smooth ice.
See lessA child sitting in an open car going at a constant speed throws a ball straight up in the air. The ball falls
When the child throws the ball straight up in the air while inside a car moving at a constant speed, the motion of the ball is influenced by both the initial velocity imparted by the child and the uniform motion of the car. Since the car is moving with a constant velocity, there are no additional foRead more
When the child throws the ball straight up in the air while inside a car moving at a constant speed, the motion of the ball is influenced by both the initial velocity imparted by the child and the uniform motion of the car. Since the car is moving with a constant velocity, there are no additional forces acting on the ball while it is in the air relative to the car. Therefore, the ball follows a simple parabolic trajectory, going vertically upwards due to the initial throw and then falling downwards, relative to the car’s frame of reference; option [C].
See lessSince the ball has no horizontal motion relative to the car, it remains directly above the child throughout its flight. As a result, when it descends, it falls back into the hands of the child, assuming the child’s hands remain in the same position throughout the motion. This is because both the child and the ball are moving at the same velocity horizontally, so there’s no relative motion between them in the horizontal direction. Consequently, the correct option is [C] in his hand, as the ball returns to the child’s hand due to the absence of any external horizontal forces acting on it within the car’s frame of reference.
The hairs of the shaving brush stick together when taken out of water. The reason for this is
The hairs of the shaving brush stick together when taken out of water primarily due to surface tension; option [A]. Surface tension arises from cohesive forces between water molecules, causing them to attract each other. When the shaving brush is submerged in water, water molecules adhere to the haiRead more
The hairs of the shaving brush stick together when taken out of water primarily due to surface tension; option [A]. Surface tension arises from cohesive forces between water molecules, causing them to attract each other. When the shaving brush is submerged in water, water molecules adhere to the hairs and create a thin film on their surface. Upon removal from water, the cohesive forces between the water molecules cause them to cling together, resulting in the hairs sticking together.
While viscosity, elasticity, and friction play roles in various phenomena, they are not the primary reasons for the hairs of the shaving brush sticking together. Viscosity refers to a fluid’s resistance to flow and does not directly affect the hairs of the brush. Elasticity pertains to the ability of a material to return to its original shape after deformation and is not relevant to the sticking of the hairs. Friction is the resistance encountered when one object slides over another, but it is not the dominant factor in this scenario.
Understanding the role of surface tension elucidates why the hairs of the shaving brush tend to stick together when removed from water, a phenomenon commonly observed in daily grooming routines.
See lessWhen kerosene oil is added to stagnant water, mosquitoes reduce because it
When kerosene oil is added to stagnant water, mosquitoes reduce because it interferes with the breathing of the larvae; option [C]. Kerosene forms a thin film on the water's surface, which blocks the larvae's access to air. Since mosquito larvae need to breathe air through a siphon at the water surfRead more
When kerosene oil is added to stagnant water, mosquitoes reduce because it interferes with the breathing of the larvae; option [C]. Kerosene forms a thin film on the water’s surface, which blocks the larvae’s access to air. Since mosquito larvae need to breathe air through a siphon at the water surface, the layer of kerosene prevents them from doing so effectively, leading to suffocation and mortality. This disruption of their respiratory process significantly impairs their ability to survive and develop into adult mosquitoes.
While kerosene does not directly poison the mosquitoes or drive them away, its presence alters the environment in a way that is inhospitable to mosquito larvae. By obstructing their access to essential air, kerosene effectively hinders their development and reproduction cycle. This method is often used as a non-toxic approach to mosquito control, as it targets the larvae rather than adult mosquitoes. Consequently, by reducing the mosquito population at the larval stage, it helps mitigate the risk of mosquito-borne diseases and discomfort caused by adult mosquitoes.
See lessDue to what reason does the shape of a rain drop become spherical?
The shape of a raindrop becomes spherical primarily due to surface tension; option [B]. Surface tension is the cohesive force between water molecules at the surface, causing them to pull inward. When a raindrop forms, surface tension acts equally in all directions, minimizing the surface area and puRead more
The shape of a raindrop becomes spherical primarily due to surface tension; option [B]. Surface tension is the cohesive force between water molecules at the surface, causing them to pull inward. When a raindrop forms, surface tension acts equally in all directions, minimizing the surface area and pulling the drop into a spherical shape. This occurs despite the influence of gravity, which tends to deform the drop slightly. While viscosity, elasticity, and gravity play roles in the behavior of raindrops, surface tension is the dominant force determining their shape. Raindrops maintain their spherical form until they encounter air resistance or other forces that may cause deformation. Understanding the interplay between surface tension and external forces helps explain the characteristic shape of raindrops and their behavior during precipitation events.
See lessWhat is the principle of purification by soap?
The principle of purification by soap is based on surface tension; option [A]. Soap molecules contain both hydrophilic and hydrophobic parts. When soap is added to water, its hydrophobic tails attach to oil and grease, while the hydrophilic heads face outward. This forms structures called micelles,Read more
The principle of purification by soap is based on surface tension; option [A]. Soap molecules contain both hydrophilic and hydrophobic parts. When soap is added to water, its hydrophobic tails attach to oil and grease, while the hydrophilic heads face outward. This forms structures called micelles, which encapsulate the dirt and oil, breaking them into smaller droplets suspended in the water. These micelles reduce the surface tension of water, allowing the trapped particles to be easily lifted away. This mechanism is essential for cleaning surfaces as it prevents the redeposition of dirt and oil onto cleaned surfaces. Therefore, the effectiveness of soap in purification is fundamentally tied to its ability to alter surface tension, facilitating the removal of contaminants and ensuring thorough cleaning across various surfaces.
See lessOil spreads on the surface of water because
Oil spreads on the surface of water primarily due to differences in surface tension between the two substances. The surface tension of water is higher than that of oil. This means that water molecules tend to stick together more strongly at the surface, forming a "skin" that resists penetration. InRead more
Oil spreads on the surface of water primarily due to differences in surface tension between the two substances. The surface tension of water is higher than that of oil. This means that water molecules tend to stick together more strongly at the surface, forming a “skin” that resists penetration. In contrast, oil molecules have weaker intermolecular forces at the surface, allowing them to spread out more easily. This phenomenon occurs despite the fact that oil is less dense than water; option [D]. Oil molecules move to the water’s surface to minimize contact with water molecules, creating a thin layer. This behavior is essential in environmental contexts, such as oil spills, where oil can spread rapidly over large areas of water. Understanding the surface tension properties of oil and water is crucial for managing and mitigating the environmental impacts of such incidents.
See lesswhat is H5N1 bird flu?
H5N1 bird flu is a subtype of influenza A virus that primarily infects birds but can also be transmitted to humans. It poses a significant threat to both animal and human health. In birds, H5N1 can cause severe illness and high mortality rates, leading to significant economic losses in the poultry iRead more
H5N1 bird flu is a subtype of influenza A virus that primarily infects birds but can also be transmitted to humans. It poses a significant threat to both animal and human health. In birds, H5N1 can cause severe illness and high mortality rates, leading to significant economic losses in the poultry industry. When humans are infected, typically through direct contact with infected birds or contaminated environments, H5N1 can result in severe respiratory illness and, in some cases, death. While human-to-human transmission of H5N1 is rare, it has the potential to lead to a widespread outbreak or pandemic if the virus undergoes genetic changes that allow for efficient transmission between people. Monitoring and control measures, including surveillance, vaccination, and biosecurity protocols, are essential for preventing and managing outbreaks of H5N1 bird flu.
See lessIn which continent is there complete absence of volcanoes?
Australia is the continent with a complete absence of volcanoes. Unlike other continents, such as Asia, Europe, and even Antarctica, which have witnessed volcanic activity, Australia lacks any active volcanic systems. This absence can be attributed to Australia's position on the tectonic plates. WhiRead more
Australia is the continent with a complete absence of volcanoes. Unlike other continents, such as Asia, Europe, and even Antarctica, which have witnessed volcanic activity, Australia lacks any active volcanic systems. This absence can be attributed to Australia’s position on the tectonic plates. While Australia has experienced volcanic activity in the distant past, particularly during the Paleozoic and Mesozoic eras, it has since become geologically stable. The continent is situated within the interior of the Indo-Australian Plate, far away from any active plate boundaries where volcanic activity typically occurs. Consequently, Australia is characterized by a lack of recent volcanic features such as volcanic peaks, lava fields, or volcanic activity, making it unique among the continents in terms of its geological profile.
See lessThrough which of the following continents do the Tropics of Cancer, Equator and Capricorn pass?
The Tropics of Cancer, Equator, and Capricorn intersect with the continent of Africa, positioning it uniquely within the global geographical framework. The Equator, an imaginary line dividing the Earth into northern and southern hemispheres, traverses through central Africa, bestowing equatorial cliRead more
The Tropics of Cancer, Equator, and Capricorn intersect with the continent of Africa, positioning it uniquely within the global geographical framework. The Equator, an imaginary line dividing the Earth into northern and southern hemispheres, traverses through central Africa, bestowing equatorial climates upon countries like the Democratic Republic of Congo and Uganda. Further north, the Tropic of Cancer cuts through northern Africa, influencing the climates of countries such as Egypt and Libya. Conversely, the Tropic of Capricorn crosses the southern part of Africa, affecting climates in nations like Namibia and Botswana. This convergence of significant latitudinal lines contributes to Africa’s diverse climate zones, ranging from tropical rainforests near the Equator to arid deserts near the Tropics, showcasing the continent’s rich geographical diversity and its profound impact on the region’s ecosystems, cultures, and societies.
See less