When two stones of different masses are dropped simultaneously from the top of a building, both stones reach the ground together; option [C]. This phenomenon occurs due to the absence of significant air resistance, and according to the principle of universal gravitation, all objects fall at the sameRead more
When two stones of different masses are dropped simultaneously from the top of a building, both stones reach the ground together; option [C]. This phenomenon occurs due to the absence of significant air resistance, and according to the principle of universal gravitation, all objects fall at the same rate regardless of their mass. Therefore, neither the smaller nor the larger stone reaches the ground before the other. The composition of the stone does not affect this outcome. This concept is a fundamental principle in physics known as the equivalence principle, which states that in a vacuum, all objects experience the same acceleration due to gravity regardless of their mass. Thus, the correct option is [C] Both the stones reach the ground together, illustrating a fundamental aspect of gravitational physics.
Mercury has the lowest density among the listed liquids; option [D]. Mercury's density is approximately 13.6 grams per cubic centimeter (g/cm³), making it much denser than the other options. Clean water typically has a density around 1 g/cm³, while salty water, which contains dissolved salts, may haRead more
Mercury has the lowest density among the listed liquids; option [D]. Mercury’s density is approximately 13.6 grams per cubic centimeter (g/cm³), making it much denser than the other options. Clean water typically has a density around 1 g/cm³, while salty water, which contains dissolved salts, may have a slightly higher density due to the added solutes. Petrol, a liquid hydrocarbon mixture used as fuel, has a density generally lower than water but higher than mercury. However, even petrol’s density is significantly higher than that of mercury. Mercury’s low density is attributed to its atomic structure, consisting of relatively large and heavy atoms closely packed together. This density difference is why mercury sinks when mixed with water, as water has a lower density. Therefore, when comparing the densities of clean water, salty water, petrol, and mercury, mercury has the lowest density, making it unique among the options provided. Thus, the correct option is [D] Mercury.
Bernoulli's theorem is based on energy conservation; option [B]. It states that in a flowing fluid, the total mechanical energy per unit mass remains constant along a streamline. This principle describes the relationship between fluid velocity, pressure, and elevation and is fundamental in fluid dynRead more
Bernoulli’s theorem is based on energy conservation; option [B]. It states that in a flowing fluid, the total mechanical energy per unit mass remains constant along a streamline. This principle describes the relationship between fluid velocity, pressure, and elevation and is fundamental in fluid dynamics, aerodynamics, and hydrodynamics. Bernoulli’s theorem helps analyze fluid flow in various engineering applications, including aircraft design, pipe flow, and hydraulic systems. It is derived from the conservation of energy principle, where the total energy of a system remains constant unless acted upon by external forces. Therefore, the correct option is [B] Energy conservation, elucidating the foundational principle upon which Bernoulli’s theorem is based.
An iron needle floats on the surface of water due to surface tension; option [B]. Surface tension arises from the cohesive forces between water molecules, particularly at the water-air interface. This cohesion creates a thin film on the water's surface with higher tension than the bulk of the liquidRead more
An iron needle floats on the surface of water due to surface tension; option [B]. Surface tension arises from the cohesive forces between water molecules, particularly at the water-air interface. This cohesion creates a thin film on the water’s surface with higher tension than the bulk of the liquid. The surface tension acts like a “skin,” supporting lightweight objects such as the iron needle, allowing it to float. Unlike other materials, the iron needle’s density is higher than that of water, so it would typically sink. However, the strong surface tension of water counteracts the needle’s weight, effectively “holding it up” on the water’s surface. This phenomenon is observed in various contexts, from small insects walking on water to certain lightweight objects floating. Therefore, the correct option is [B] Due to surface tension, as it is the cohesive force at the water’s surface that enables the iron needle to float rather than sink.
Absorption of ink by blotting paper involves the capillary reaction phenomenon; option [B]. Capillary action occurs due to the cohesive and adhesive forces between the liquid molecules and the fibers of the paper. This interaction causes the ink to be drawn upward through the small pores in the papeRead more
Absorption of ink by blotting paper involves the capillary reaction phenomenon; option [B]. Capillary action occurs due to the cohesive and adhesive forces between the liquid molecules and the fibers of the paper. This interaction causes the ink to be drawn upward through the small pores in the paper, facilitating its absorption. Capillary action is crucial in processes like ink absorption in blotting paper, where it efficiently pulls the ink into the paper fibers. Viscosity of the ink refers to its resistance to flow and is not directly related to the adsorption process. Diffusion of ink through blotting involves the movement of ink molecules through the paper, which is not the primary mechanism in ink absorption by blotting paper. Siphon action requires a continuous flow of liquid, which is not applicable to the absorption of ink by blotting paper. Therefore, the correct option is [B] Capillary Reaction phenomenon.
Action and reaction have the same magnitude and opposite directions; option [D]. According to Newton's third law of motion, when one object exerts a force on another object (action), the second object exerts an equal but opposite force on the first object (reaction). These forces act on different obRead more
Action and reaction have the same magnitude and opposite directions; option [D]. According to Newton’s third law of motion, when one object exerts a force on another object (action), the second object exerts an equal but opposite force on the first object (reaction). These forces act on different objects, have equal magnitudes, and opposite directions. Therefore, all options are correct: [A] Work on two different objects, [B] Have the same magnitude, and [C] Have opposite directions. This fundamental principle of action and reaction is essential in understanding the dynamics of interactions between objects and is applicable in various fields of physics and engineering. It elucidates how forces are transmitted between objects and plays a critical role in analyzing and predicting the motion of systems governed by Newtonian mechanics.
To cover the maximum horizontal distance, a ball should be thrown at a 45° angle from the horizontal; option [D]. At this angle, the horizontal and vertical components of the initial velocity are equal, leading to the greatest range for a projectile launched with the same initial speed. Therefore, tRead more
To cover the maximum horizontal distance, a ball should be thrown at a 45° angle from the horizontal; option [D]. At this angle, the horizontal and vertical components of the initial velocity are equal, leading to the greatest range for a projectile launched with the same initial speed. Therefore, the correct option is [D] 45°. This principle is derived from the equations of projectile motion and is applicable in various contexts, from sports like basketball and javelin throwing to engineering applications such as projectile motion calculations. Understanding the optimal launch angle for maximum range is essential for achieving desired distances in projectile motion scenarios, making it a fundamental concept in physics and practical applications. Thus, launching the ball at a 45° angle ensures it travels the farthest horizontally compared to other angles listed.
Angstrom measures wavelength; option [B]. It is a unit of length used predominantly in fields such as atomic physics, spectroscopy, and crystallography. Named after the Swedish physicist Anders Jonas Ångström, 1 Angstrom is equivalent to 0.1 nanometers or 10^(-10)meters. This unit is particularly usRead more
Angstrom measures wavelength; option [B]. It is a unit of length used predominantly in fields such as atomic physics, spectroscopy, and crystallography. Named after the Swedish physicist Anders Jonas Ångström, 1 Angstrom is equivalent to 0.1 nanometers or 10^(-10)meters. This unit is particularly useful in expressing the sizes of atoms and molecules, as well as the wavelengths of electromagnetic radiation, including light. In spectroscopy, for instance, Angstroms are commonly used to measure the wavelengths of spectral lines emitted or absorbed by atoms and molecules. This allows scientists to analyze the composition and properties of substances based on the characteristic wavelengths of light they emit or absorb. Therefore, Angstrom serves as a fundamental unit for quantifying the spatial periodicity of waves and the distances between atomic or molecular structures. Consequently, the correct option is [B] Wavelength, as Angstroms are primarily utilized to measure the lengths of waves, whether they are electromagnetic waves or the characteristic sizes of atomic and molecular structures.
Before Newton, Varahamihir, an ancient Indian astronomer and mathematician, proposed that all objects gravitate towards the Earth; option [B]. He lived during the 6th century CE and contributed significantly to the fields of astronomy and mathematics. Varahamihir's work laid the foundation for underRead more
Before Newton, Varahamihir, an ancient Indian astronomer and mathematician, proposed that all objects gravitate towards the Earth; option [B]. He lived during the 6th century CE and contributed significantly to the fields of astronomy and mathematics. Varahamihir’s work laid the foundation for understanding gravitational forces, predating Newton’s discoveries by several centuries. Therefore, the correct option is [B] Varahamihir. His insights into the gravitational attraction of objects towards the Earth demonstrate the early recognition of this fundamental force in the natural world, highlighting the rich history of scientific inquiry and discovery in ancient India. Varahamihir’s contributions to astronomy and mathematics continue to be recognized for their significance in shaping our understanding of the universe and its physical laws, including the force of gravity.
On heating an object, the speed of its molecules will increase. Heating transfers thermal energy to the molecules, causing them to move more rapidly; option [A]. This increase in molecular motion results in a rise in temperature and expansion of the object. Therefore, the correct option is [A] willRead more
On heating an object, the speed of its molecules will increase. Heating transfers thermal energy to the molecules, causing them to move more rapidly; option [A]. This increase in molecular motion results in a rise in temperature and expansion of the object. Therefore, the correct option is [A] will increase, aligning with the principles of kinetic theory, which state that the average kinetic energy of molecules in a substance is directly proportional to its temperature. As the molecules gain energy, they move faster, leading to an increase in speed. This phenomenon is observed in various contexts, from the expansion of gases to the melting of solids and the vaporization of liquids. Thus, heating induces greater molecular motion, demonstrating the relationship between thermal energy and the speed of molecules in a substance.
Two stones of different masses are dropped simultaneously from the top of a building
When two stones of different masses are dropped simultaneously from the top of a building, both stones reach the ground together; option [C]. This phenomenon occurs due to the absence of significant air resistance, and according to the principle of universal gravitation, all objects fall at the sameRead more
When two stones of different masses are dropped simultaneously from the top of a building, both stones reach the ground together; option [C]. This phenomenon occurs due to the absence of significant air resistance, and according to the principle of universal gravitation, all objects fall at the same rate regardless of their mass. Therefore, neither the smaller nor the larger stone reaches the ground before the other. The composition of the stone does not affect this outcome. This concept is a fundamental principle in physics known as the equivalence principle, which states that in a vacuum, all objects experience the same acceleration due to gravity regardless of their mass. Thus, the correct option is [C] Both the stones reach the ground together, illustrating a fundamental aspect of gravitational physics.
See lessWhich of the following liquids has the lowest density?
Mercury has the lowest density among the listed liquids; option [D]. Mercury's density is approximately 13.6 grams per cubic centimeter (g/cm³), making it much denser than the other options. Clean water typically has a density around 1 g/cm³, while salty water, which contains dissolved salts, may haRead more
Mercury has the lowest density among the listed liquids; option [D]. Mercury’s density is approximately 13.6 grams per cubic centimeter (g/cm³), making it much denser than the other options. Clean water typically has a density around 1 g/cm³, while salty water, which contains dissolved salts, may have a slightly higher density due to the added solutes. Petrol, a liquid hydrocarbon mixture used as fuel, has a density generally lower than water but higher than mercury. However, even petrol’s density is significantly higher than that of mercury. Mercury’s low density is attributed to its atomic structure, consisting of relatively large and heavy atoms closely packed together. This density difference is why mercury sinks when mixed with water, as water has a lower density. Therefore, when comparing the densities of clean water, salty water, petrol, and mercury, mercury has the lowest density, making it unique among the options provided. Thus, the correct option is [D] Mercury.
See lessBernoulli’s theorem is based on
Bernoulli's theorem is based on energy conservation; option [B]. It states that in a flowing fluid, the total mechanical energy per unit mass remains constant along a streamline. This principle describes the relationship between fluid velocity, pressure, and elevation and is fundamental in fluid dynRead more
Bernoulli’s theorem is based on energy conservation; option [B]. It states that in a flowing fluid, the total mechanical energy per unit mass remains constant along a streamline. This principle describes the relationship between fluid velocity, pressure, and elevation and is fundamental in fluid dynamics, aerodynamics, and hydrodynamics. Bernoulli’s theorem helps analyze fluid flow in various engineering applications, including aircraft design, pipe flow, and hydraulic systems. It is derived from the conservation of energy principle, where the total energy of a system remains constant unless acted upon by external forces. Therefore, the correct option is [B] Energy conservation, elucidating the foundational principle upon which Bernoulli’s theorem is based.
See lessWhy does an iron needle float on the surface of water?
An iron needle floats on the surface of water due to surface tension; option [B]. Surface tension arises from the cohesive forces between water molecules, particularly at the water-air interface. This cohesion creates a thin film on the water's surface with higher tension than the bulk of the liquidRead more
An iron needle floats on the surface of water due to surface tension; option [B]. Surface tension arises from the cohesive forces between water molecules, particularly at the water-air interface. This cohesion creates a thin film on the water’s surface with higher tension than the bulk of the liquid. The surface tension acts like a “skin,” supporting lightweight objects such as the iron needle, allowing it to float. Unlike other materials, the iron needle’s density is higher than that of water, so it would typically sink. However, the strong surface tension of water counteracts the needle’s weight, effectively “holding it up” on the water’s surface. This phenomenon is observed in various contexts, from small insects walking on water to certain lightweight objects floating. Therefore, the correct option is [B] Due to surface tension, as it is the cohesive force at the water’s surface that enables the iron needle to float rather than sink.
See lessAbsorption of ink by blotting paper involves
Absorption of ink by blotting paper involves the capillary reaction phenomenon; option [B]. Capillary action occurs due to the cohesive and adhesive forces between the liquid molecules and the fibers of the paper. This interaction causes the ink to be drawn upward through the small pores in the papeRead more
Absorption of ink by blotting paper involves the capillary reaction phenomenon; option [B]. Capillary action occurs due to the cohesive and adhesive forces between the liquid molecules and the fibers of the paper. This interaction causes the ink to be drawn upward through the small pores in the paper, facilitating its absorption. Capillary action is crucial in processes like ink absorption in blotting paper, where it efficiently pulls the ink into the paper fibers. Viscosity of the ink refers to its resistance to flow and is not directly related to the adsorption process. Diffusion of ink through blotting involves the movement of ink molecules through the paper, which is not the primary mechanism in ink absorption by blotting paper. Siphon action requires a continuous flow of liquid, which is not applicable to the absorption of ink by blotting paper. Therefore, the correct option is [B] Capillary Reaction phenomenon.
See lessAction and reaction
Action and reaction have the same magnitude and opposite directions; option [D]. According to Newton's third law of motion, when one object exerts a force on another object (action), the second object exerts an equal but opposite force on the first object (reaction). These forces act on different obRead more
Action and reaction have the same magnitude and opposite directions; option [D]. According to Newton’s third law of motion, when one object exerts a force on another object (action), the second object exerts an equal but opposite force on the first object (reaction). These forces act on different objects, have equal magnitudes, and opposite directions. Therefore, all options are correct: [A] Work on two different objects, [B] Have the same magnitude, and [C] Have opposite directions. This fundamental principle of action and reaction is essential in understanding the dynamics of interactions between objects and is applicable in various fields of physics and engineering. It elucidates how forces are transmitted between objects and plays a critical role in analyzing and predicting the motion of systems governed by Newtonian mechanics.
See lessAt what angle should a ball be thrown from the horizontal so that it can cover the maximum horizontal distance?
To cover the maximum horizontal distance, a ball should be thrown at a 45° angle from the horizontal; option [D]. At this angle, the horizontal and vertical components of the initial velocity are equal, leading to the greatest range for a projectile launched with the same initial speed. Therefore, tRead more
To cover the maximum horizontal distance, a ball should be thrown at a 45° angle from the horizontal; option [D]. At this angle, the horizontal and vertical components of the initial velocity are equal, leading to the greatest range for a projectile launched with the same initial speed. Therefore, the correct option is [D] 45°. This principle is derived from the equations of projectile motion and is applicable in various contexts, from sports like basketball and javelin throwing to engineering applications such as projectile motion calculations. Understanding the optimal launch angle for maximum range is essential for achieving desired distances in projectile motion scenarios, making it a fundamental concept in physics and practical applications. Thus, launching the ball at a 45° angle ensures it travels the farthest horizontally compared to other angles listed.
See lessWhat does Angstrom measure?
Angstrom measures wavelength; option [B]. It is a unit of length used predominantly in fields such as atomic physics, spectroscopy, and crystallography. Named after the Swedish physicist Anders Jonas Ångström, 1 Angstrom is equivalent to 0.1 nanometers or 10^(-10)meters. This unit is particularly usRead more
Angstrom measures wavelength; option [B]. It is a unit of length used predominantly in fields such as atomic physics, spectroscopy, and crystallography. Named after the Swedish physicist Anders Jonas Ångström, 1 Angstrom is equivalent to 0.1 nanometers or 10^(-10)meters. This unit is particularly useful in expressing the sizes of atoms and molecules, as well as the wavelengths of electromagnetic radiation, including light. In spectroscopy, for instance, Angstroms are commonly used to measure the wavelengths of spectral lines emitted or absorbed by atoms and molecules. This allows scientists to analyze the composition and properties of substances based on the characteristic wavelengths of light they emit or absorb. Therefore, Angstrom serves as a fundamental unit for quantifying the spatial periodicity of waves and the distances between atomic or molecular structures. Consequently, the correct option is [B] Wavelength, as Angstroms are primarily utilized to measure the lengths of waves, whether they are electromagnetic waves or the characteristic sizes of atomic and molecular structures.
See lessWho of the following had told before Newton that all objects gravitate towards the earth?
Before Newton, Varahamihir, an ancient Indian astronomer and mathematician, proposed that all objects gravitate towards the Earth; option [B]. He lived during the 6th century CE and contributed significantly to the fields of astronomy and mathematics. Varahamihir's work laid the foundation for underRead more
Before Newton, Varahamihir, an ancient Indian astronomer and mathematician, proposed that all objects gravitate towards the Earth; option [B]. He lived during the 6th century CE and contributed significantly to the fields of astronomy and mathematics. Varahamihir’s work laid the foundation for understanding gravitational forces, predating Newton’s discoveries by several centuries. Therefore, the correct option is [B] Varahamihir. His insights into the gravitational attraction of objects towards the Earth demonstrate the early recognition of this fundamental force in the natural world, highlighting the rich history of scientific inquiry and discovery in ancient India. Varahamihir’s contributions to astronomy and mathematics continue to be recognized for their significance in shaping our understanding of the universe and its physical laws, including the force of gravity.
See lessOn heating an object, the speed of its molecules
On heating an object, the speed of its molecules will increase. Heating transfers thermal energy to the molecules, causing them to move more rapidly; option [A]. This increase in molecular motion results in a rise in temperature and expansion of the object. Therefore, the correct option is [A] willRead more
On heating an object, the speed of its molecules will increase. Heating transfers thermal energy to the molecules, causing them to move more rapidly; option [A]. This increase in molecular motion results in a rise in temperature and expansion of the object. Therefore, the correct option is [A] will increase, aligning with the principles of kinetic theory, which state that the average kinetic energy of molecules in a substance is directly proportional to its temperature. As the molecules gain energy, they move faster, leading to an increase in speed. This phenomenon is observed in various contexts, from the expansion of gases to the melting of solids and the vaporization of liquids. Thus, heating induces greater molecular motion, demonstrating the relationship between thermal energy and the speed of molecules in a substance.
See less