The reason for the floating of clouds in the atmosphere is density (D). Clouds consist of tiny water droplets or ice crystals that are less dense than the surrounding air. This lower density causes the clouds to float or remain suspended in the atmosphere. Temperature (A), velocity (B), and pressureRead more
The reason for the floating of clouds in the atmosphere is density (D). Clouds consist of tiny water droplets or ice crystals that are less dense than the surrounding air. This lower density causes the clouds to float or remain suspended in the atmosphere. Temperature (A), velocity (B), and pressure (C) can influence cloud formation and movement but are not the primary reasons for their floating. Density, on the other hand, directly affects the buoyancy of clouds, as they rise and fall within the atmosphere based on changes in temperature and pressure gradients. Thus, clouds float due to their lower density compared to the surrounding air, making option (D) the correct choice for explaining the phenomenon of cloud floating in the atmosphere.
Approximately 1/10 part of an iceberg floating in the sea remains above the surface of the sea (B). This is due to Archimedes' principle, which states that the buoyant force acting on a submerged object is equal to the weight of the fluid displaced by the object. Icebergs are made of freshwater ice,Read more
Approximately 1/10 part of an iceberg floating in the sea remains above the surface of the sea (B). This is due to Archimedes’ principle, which states that the buoyant force acting on a submerged object is equal to the weight of the fluid displaced by the object. Icebergs are made of freshwater ice, which has a density of about 0.92 g/cm³, while seawater has a density of about 1.025 g/cm³. Because the density of ice is lower than that of seawater, only about 1/10 of the iceberg’s volume is above the surface, while the rest is submerged. This ratio can vary depending on factors such as the iceberg’s shape and density distribution. Option (B) 1/10 accurately represents this fraction, making it the correct answer.
The wall below the dam is made thick because the pressure of the fluid increases with increasing depth (A). This is due to the weight of the fluid above exerting a force on the lower levels. A thicker wall is needed to withstand the greater force exerted by the fluid against it as the depth increaseRead more
The wall below the dam is made thick because the pressure of the fluid increases with increasing depth (A). This is due to the weight of the fluid above exerting a force on the lower levels. A thicker wall is needed to withstand the greater force exerted by the fluid against it as the depth increases. This principle is described by Pascal’s law, which states that pressure applied to a fluid in a confined space is transmitted undiminished throughout the fluid. Therefore, as the depth below the dam increases, the pressure exerted by the water against the wall also increases. Option (A) accurately reflects this relationship between pressure and depth, making it the correct choice for explaining the necessity of a thick wall below the dam.
Skating on ice shows that on increasing the pressure, the melting point of ice decreases (B). When pressure is applied by the skater's weight, it lowers the melting point of the ice underneath the skate blades. This occurs because pressure causes the ice molecules to come closer together, making itRead more
Skating on ice shows that on increasing the pressure, the melting point of ice decreases (B). When pressure is applied by the skater’s weight, it lowers the melting point of the ice underneath the skate blades. This occurs because pressure causes the ice molecules to come closer together, making it harder for them to maintain their solid structure. As a result, the ice briefly melts, forming a thin layer of water between the skate blades and the ice surface. This reduced melting point allows for easier gliding of the skates on the ice. Option (B) accurately reflects this phenomenon, indicating that the melting point of ice decreases under increased pressure, making it the correct choice to explain the observation of skating on ice.
The ball keeps dancing in the water spray at intersections because due to higher velocity of water, pressure becomes higher (B). As the water exits the nozzle at high speed, its kinetic energy increases, resulting in an increase in pressure according to Bernoulli's principle. This higher pressure arRead more
The ball keeps dancing in the water spray at intersections because due to higher velocity of water, pressure becomes higher (B). As the water exits the nozzle at high speed, its kinetic energy increases, resulting in an increase in pressure according to Bernoulli’s principle. This higher pressure around the ball creates a force that propels it and causes it to dance in the spray. Options (A), (C), and (D) are not relevant to the phenomenon described. Surface tension (C) typically refers to the cohesive forces between liquid molecules at the surface, not applicable to the situation. Viscosity (D) relates to a fluid’s resistance to flow, which does not directly influence the ball’s dancing behavior. Therefore, option (B) accurately explains the mechanism behind the ball’s movement in the water spray at intersections.
A heavy iceberg melts at the bottom rather than the top because the melting point decreases due to the pressure of the lower layer being higher (B). As the weight of the iceberg compresses the lower layers, the pressure increases, lowering the melting point of ice according to the principle of pressRead more
A heavy iceberg melts at the bottom rather than the top because the melting point decreases due to the pressure of the lower layer being higher (B). As the weight of the iceberg compresses the lower layers, the pressure increases, lowering the melting point of ice according to the principle of pressure melting. This causes the ice at the bottom to melt first, despite the fact that the temperature may be colder at greater depths. Options (A) and (C) are incorrect as they do not accurately explain the phenomenon. While the temperature gradient within the iceberg may play a role, it is primarily the pressure-induced decrease in melting point that causes bottom-up melting in heavy icebergs. Therefore, option (B) provides the most appropriate explanation for why heavy icebergs melt at the bottom.
A person trapped in a swamp is advised to lie down because as the area increases, the pressure decreases (A). When lying down, the person's weight is distributed over a larger surface area, reducing the pressure exerted on the swamp's surface. Option (A) accurately explains the reason behind this adRead more
A person trapped in a swamp is advised to lie down because as the area increases, the pressure decreases (A). When lying down, the person’s weight is distributed over a larger surface area, reducing the pressure exerted on the swamp’s surface. Option (A) accurately explains the reason behind this advice. Options (B) and (C) are incorrect as they do not reflect the relationship between pressure and area accurately. Option (D) is also incorrect as it suggests that all options are valid, which is not the case. Therefore, option (A) provides the most appropriate explanation for why a person trapped in a swamp should lie down, as it describes the physical principle of pressure distribution and its effect on sinking in soft surfaces like swamps.
Milk becomes sour primarily due to the action of bacteria. Specifically, lactic acid bacteria such as Lactobacillus and Streptococcus ferment the lactose (milk sugar) present in the milk, converting it into lactic acid. This acidification changes the pH of the milk, leading to the sour taste and cauRead more
Milk becomes sour primarily due to the action of bacteria. Specifically, lactic acid bacteria such as Lactobacillus and Streptococcus ferment the lactose (milk sugar) present in the milk, converting it into lactic acid. This acidification changes the pH of the milk, leading to the sour taste and causing the proteins in the milk to coagulate, forming curds. These bacteria are naturally present in milk and other dairy products, and their activity is essential in the production of sour milk, yogurt, and cheese. The fermentation process not only changes the flavor and texture of the milk but also increases its shelf life by inhibiting the growth of spoilage organisms. While bacteria are the primary agents of milk souring, the other options, such as protozoa, viruses, and nematodes, do not play a significant role in this process.
Lactobacillus is the microorganism that plays a crucial role in the process of making curd. When added to milk, it begins a fermentation process where it converts lactose, the natural sugar in milk, into lactic acid. This change in the milk's composition leads to the thickening of the milk and the fRead more
Lactobacillus is the microorganism that plays a crucial role in the process of making curd. When added to milk, it begins a fermentation process where it converts lactose, the natural sugar in milk, into lactic acid. This change in the milk’s composition leads to the thickening of the milk and the formation of curd. The lactic acid also gives curd its distinct sour taste, which many people find appealing. This bacterium is naturally found in milk and dairy products, so it serves as an effective starter culture for curd production. Aside from its role in curd making, Lactobacillus also contributes to the health benefits of curd, as it is known to be beneficial for gut health and digestion. The process is simple and has been practiced for centuries, making curd a staple food in many cultures.
Refrigeration helps in food preservation by reducing the rate of biochemical reactions. By lowering the temperature, refrigeration slows down the growth and activity of bacteria and other microorganisms that can cause spoilage and foodborne illnesses. This method also slows down the rate of enzyme aRead more
Refrigeration helps in food preservation by reducing the rate of biochemical reactions. By lowering the temperature, refrigeration slows down the growth and activity of bacteria and other microorganisms that can cause spoilage and foodborne illnesses. This method also slows down the rate of enzyme activity in foods, which can affect flavor, texture, and overall quality. By keeping the food at a lower temperature, refrigeration helps maintain freshness and extend shelf life. While refrigeration does not necessarily kill bacteria, it inhibits their reproduction, allowing food to be safely stored for a longer period. Additionally, refrigeration can help prevent the growth of mold and yeast on perishable items. Properly storing food in the refrigerator is an effective way to preserve its nutritional value and prevent waste.
The reason for floating of clouds in the atmosphere is
The reason for the floating of clouds in the atmosphere is density (D). Clouds consist of tiny water droplets or ice crystals that are less dense than the surrounding air. This lower density causes the clouds to float or remain suspended in the atmosphere. Temperature (A), velocity (B), and pressureRead more
The reason for the floating of clouds in the atmosphere is density (D). Clouds consist of tiny water droplets or ice crystals that are less dense than the surrounding air. This lower density causes the clouds to float or remain suspended in the atmosphere. Temperature (A), velocity (B), and pressure (C) can influence cloud formation and movement but are not the primary reasons for their floating. Density, on the other hand, directly affects the buoyancy of clouds, as they rise and fall within the atmosphere based on changes in temperature and pressure gradients. Thus, clouds float due to their lower density compared to the surrounding air, making option (D) the correct choice for explaining the phenomenon of cloud floating in the atmosphere.
See lessHow much part of the iceberg floating in the sea remains above the surface of the sea?
Approximately 1/10 part of an iceberg floating in the sea remains above the surface of the sea (B). This is due to Archimedes' principle, which states that the buoyant force acting on a submerged object is equal to the weight of the fluid displaced by the object. Icebergs are made of freshwater ice,Read more
Approximately 1/10 part of an iceberg floating in the sea remains above the surface of the sea (B). This is due to Archimedes’ principle, which states that the buoyant force acting on a submerged object is equal to the weight of the fluid displaced by the object. Icebergs are made of freshwater ice, which has a density of about 0.92 g/cm³, while seawater has a density of about 1.025 g/cm³. Because the density of ice is lower than that of seawater, only about 1/10 of the iceberg’s volume is above the surface, while the rest is submerged. This ratio can vary depending on factors such as the iceberg’s shape and density distribution. Option (B) 1/10 accurately represents this fraction, making it the correct answer.
See lessThe wall below the dam is made thick because
The wall below the dam is made thick because the pressure of the fluid increases with increasing depth (A). This is due to the weight of the fluid above exerting a force on the lower levels. A thicker wall is needed to withstand the greater force exerted by the fluid against it as the depth increaseRead more
The wall below the dam is made thick because the pressure of the fluid increases with increasing depth (A). This is due to the weight of the fluid above exerting a force on the lower levels. A thicker wall is needed to withstand the greater force exerted by the fluid against it as the depth increases. This principle is described by Pascal’s law, which states that pressure applied to a fluid in a confined space is transmitted undiminished throughout the fluid. Therefore, as the depth below the dam increases, the pressure exerted by the water against the wall also increases. Option (A) accurately reflects this relationship between pressure and depth, making it the correct choice for explaining the necessity of a thick wall below the dam.
See lessSkating on ice shows that on increasing the pressure the melting point of ice
Skating on ice shows that on increasing the pressure, the melting point of ice decreases (B). When pressure is applied by the skater's weight, it lowers the melting point of the ice underneath the skate blades. This occurs because pressure causes the ice molecules to come closer together, making itRead more
Skating on ice shows that on increasing the pressure, the melting point of ice decreases (B). When pressure is applied by the skater’s weight, it lowers the melting point of the ice underneath the skate blades. This occurs because pressure causes the ice molecules to come closer together, making it harder for them to maintain their solid structure. As a result, the ice briefly melts, forming a thin layer of water between the skate blades and the ice surface. This reduced melting point allows for easier gliding of the skates on the ice. Option (B) accurately reflects this phenomenon, indicating that the melting point of ice decreases under increased pressure, making it the correct choice to explain the observation of skating on ice.
See lessThe ball keeps dancing in the water spray at intersections because
The ball keeps dancing in the water spray at intersections because due to higher velocity of water, pressure becomes higher (B). As the water exits the nozzle at high speed, its kinetic energy increases, resulting in an increase in pressure according to Bernoulli's principle. This higher pressure arRead more
The ball keeps dancing in the water spray at intersections because due to higher velocity of water, pressure becomes higher (B). As the water exits the nozzle at high speed, its kinetic energy increases, resulting in an increase in pressure according to Bernoulli’s principle. This higher pressure around the ball creates a force that propels it and causes it to dance in the spray. Options (A), (C), and (D) are not relevant to the phenomenon described. Surface tension (C) typically refers to the cohesive forces between liquid molecules at the surface, not applicable to the situation. Viscosity (D) relates to a fluid’s resistance to flow, which does not directly influence the ball’s dancing behavior. Therefore, option (B) accurately explains the mechanism behind the ball’s movement in the water spray at intersections.
See lessA heavy iceberg melts at the bottom rather than the top, because
A heavy iceberg melts at the bottom rather than the top because the melting point decreases due to the pressure of the lower layer being higher (B). As the weight of the iceberg compresses the lower layers, the pressure increases, lowering the melting point of ice according to the principle of pressRead more
A heavy iceberg melts at the bottom rather than the top because the melting point decreases due to the pressure of the lower layer being higher (B). As the weight of the iceberg compresses the lower layers, the pressure increases, lowering the melting point of ice according to the principle of pressure melting. This causes the ice at the bottom to melt first, despite the fact that the temperature may be colder at greater depths. Options (A) and (C) are incorrect as they do not accurately explain the phenomenon. While the temperature gradient within the iceberg may play a role, it is primarily the pressure-induced decrease in melting point that causes bottom-up melting in heavy icebergs. Therefore, option (B) provides the most appropriate explanation for why heavy icebergs melt at the bottom.
See lessA person trapped in a swamp is advised to lie down because
A person trapped in a swamp is advised to lie down because as the area increases, the pressure decreases (A). When lying down, the person's weight is distributed over a larger surface area, reducing the pressure exerted on the swamp's surface. Option (A) accurately explains the reason behind this adRead more
A person trapped in a swamp is advised to lie down because as the area increases, the pressure decreases (A). When lying down, the person’s weight is distributed over a larger surface area, reducing the pressure exerted on the swamp’s surface. Option (A) accurately explains the reason behind this advice. Options (B) and (C) are incorrect as they do not reflect the relationship between pressure and area accurately. Option (D) is also incorrect as it suggests that all options are valid, which is not the case. Therefore, option (A) provides the most appropriate explanation for why a person trapped in a swamp should lie down, as it describes the physical principle of pressure distribution and its effect on sinking in soft surfaces like swamps.
See lessBy which of the following milk becomes sour?
Milk becomes sour primarily due to the action of bacteria. Specifically, lactic acid bacteria such as Lactobacillus and Streptococcus ferment the lactose (milk sugar) present in the milk, converting it into lactic acid. This acidification changes the pH of the milk, leading to the sour taste and cauRead more
Milk becomes sour primarily due to the action of bacteria. Specifically, lactic acid bacteria such as Lactobacillus and Streptococcus ferment the lactose (milk sugar) present in the milk, converting it into lactic acid. This acidification changes the pH of the milk, leading to the sour taste and causing the proteins in the milk to coagulate, forming curds. These bacteria are naturally present in milk and other dairy products, and their activity is essential in the production of sour milk, yogurt, and cheese. The fermentation process not only changes the flavor and texture of the milk but also increases its shelf life by inhibiting the growth of spoilage organisms. While bacteria are the primary agents of milk souring, the other options, such as protozoa, viruses, and nematodes, do not play a significant role in this process.
See lessWhich of the following microorganisms is used in making curd?
Lactobacillus is the microorganism that plays a crucial role in the process of making curd. When added to milk, it begins a fermentation process where it converts lactose, the natural sugar in milk, into lactic acid. This change in the milk's composition leads to the thickening of the milk and the fRead more
Lactobacillus is the microorganism that plays a crucial role in the process of making curd. When added to milk, it begins a fermentation process where it converts lactose, the natural sugar in milk, into lactic acid. This change in the milk’s composition leads to the thickening of the milk and the formation of curd. The lactic acid also gives curd its distinct sour taste, which many people find appealing. This bacterium is naturally found in milk and dairy products, so it serves as an effective starter culture for curd production. Aside from its role in curd making, Lactobacillus also contributes to the health benefits of curd, as it is known to be beneficial for gut health and digestion. The process is simple and has been practiced for centuries, making curd a staple food in many cultures.
See lessRefrigeration helps in food preservation by
Refrigeration helps in food preservation by reducing the rate of biochemical reactions. By lowering the temperature, refrigeration slows down the growth and activity of bacteria and other microorganisms that can cause spoilage and foodborne illnesses. This method also slows down the rate of enzyme aRead more
Refrigeration helps in food preservation by reducing the rate of biochemical reactions. By lowering the temperature, refrigeration slows down the growth and activity of bacteria and other microorganisms that can cause spoilage and foodborne illnesses. This method also slows down the rate of enzyme activity in foods, which can affect flavor, texture, and overall quality. By keeping the food at a lower temperature, refrigeration helps maintain freshness and extend shelf life. While refrigeration does not necessarily kill bacteria, it inhibits their reproduction, allowing food to be safely stored for a longer period. Additionally, refrigeration can help prevent the growth of mold and yeast on perishable items. Properly storing food in the refrigerator is an effective way to preserve its nutritional value and prevent waste.
See less