As we move from the equator towards the poles, the value of g decreases (B). This is due to the centrifugal force caused by Earth's rotation, which is greatest at the equator and decreases towards the poles. Additionally, the shape of the Earth is not a perfect sphere; it's slightly flattened at theRead more
As we move from the equator towards the poles, the value of g decreases (B). This is due to the centrifugal force caused by Earth’s rotation, which is greatest at the equator and decreases towards the poles. Additionally, the shape of the Earth is not a perfect sphere; it’s slightly flattened at the poles and bulging at the equator. This variation in distance from the Earth’s center also affects the gravitational force. As we move towards the poles, we are closer to the Earth’s center, resulting in a stronger gravitational force. However, this increase is offset by the decrease in centrifugal force, leading to a net decrease in the value of g. This decrease is not constant but varies gradually as we move from the equator towards the poles, reaching its maximum value at the poles. Therefore, the correct option is (B) decreases.
Body weight varies with location on Earth's surface due to differences in gravitational acceleration. It is not the same everywhere on Earth's surface. At the poles (B), gravity is stronger because objects are closer to the Earth's center. At the equator, the centrifugal force caused by Earth's rotaRead more
Body weight varies with location on Earth’s surface due to differences in gravitational acceleration. It is not the same everywhere on Earth’s surface. At the poles (B), gravity is stronger because objects are closer to the Earth’s center. At the equator, the centrifugal force caused by Earth’s rotation counteracts some of the gravitational force, resulting in slightly lower weight. Therefore, body weight is maximum at the poles and slightly lower at the equator. Additionally, weight can vary with altitude. On hills (D), the distance from the Earth’s center is slightly greater compared to plains, resulting in slightly lower weight. However, this difference is generally negligible unless at extreme altitudes. Thus, body weight is not the same everywhere, being maximum at the poles and slightly lower at the equator.
An astronaut can jump higher on the lunar surface than on the Earth's surface because the force of gravity on the lunar surface is much less compared to the Earth's surface (C). This weaker gravity allows the astronaut to exert less downward force on the lunar surface, enabling them to achieve greatRead more
An astronaut can jump higher on the lunar surface than on the Earth’s surface because the force of gravity on the lunar surface is much less compared to the Earth’s surface (C). This weaker gravity allows the astronaut to exert less downward force on the lunar surface, enabling them to achieve greater height in their jump. While the astronaut is not weightless on the Moon (A), there is less gravitational pull due to the Moon’s smaller mass (D), but this difference primarily accounts for the discrepancy in weight, not the ability to jump higher. The absence of atmosphere on the Moon (B) does not significantly affect the astronaut’s ability to jump higher, as it primarily influences air resistance rather than gravitational force. Thus, the correct option is (C) The force of gravity on the lunar surface is very less as compared to the Earth’s surface.
The work done to hold a weight of 20 kg at a height of 1 m above the ground is zero Joules (D). Work is defined as the product of force and displacement in the direction of the force. When holding an object stationary, like in this scenario, there is no displacement; thus, no work is done against grRead more
The work done to hold a weight of 20 kg at a height of 1 m above the ground is zero Joules (D). Work is defined as the product of force and displacement in the direction of the force. When holding an object stationary, like in this scenario, there is no displacement; thus, no work is done against gravity. While the weight of the object is 20 kg, and the force due to gravity is approximately 9.81 m/s² (981 N/kg), the vertical displacement is zero since the object is held at a constant height. Therefore, the work done is zero. Options (A), (B), and (C) are incorrect because they imply that work is being done, but in reality, no displacement occurs when holding the weight stationary at a constant height above the ground.
If a person pushes a wall but fails to displace it, then he does no work (A). In physics, work is defined as the product of force and displacement in the direction of the force. When there is no displacement, regardless of the magnitude of the force applied, the work done is zero. Even though the peRead more
If a person pushes a wall but fails to displace it, then he does no work (A). In physics, work is defined as the product of force and displacement in the direction of the force. When there is no displacement, regardless of the magnitude of the force applied, the work done is zero. Even though the person exerts force against the wall, if the wall does not move, there is no change in the wall’s position, and hence no work is accomplished. Option (B) is incorrect because negative work implies that energy is being taken away from the system, which doesn’t apply here. Option (C) implies some positive work, but there’s no work done if there’s no displacement. Option (D) is incorrect because maximum work would imply achieving the greatest possible displacement, which isn’t the case if the wall remains stationary. Therefore, the correct option is (A) No work.
A person climbing a hill leans forward to increase stability (D). Leaning forward shifts the center of mass towards the hillside, enhancing balance and reducing the risk of falling backward. This posture allows the individual to maintain a more stable foothold, minimizing the chance of slipping. AddRead more
A person climbing a hill leans forward to increase stability (D). Leaning forward shifts the center of mass towards the hillside, enhancing balance and reducing the risk of falling backward. This posture allows the individual to maintain a more stable foothold, minimizing the chance of slipping. Additionally, leaning forward enables better utilization of leg muscles, providing more power for propulsion uphill. It also reduces the strain on the back by distributing the load more evenly across the body. While leaning forward may contribute to a perception of increased speed, its primary purpose is to enhance stability and safety during the ascent. Therefore, the correct option is (D) to increase stability, as it aligns with the biomechanical advantages and safety considerations associated with leaning forward while climbing a hill.
The historical tower of Pisa does not fall even though it is tilted because the vertical line passing through its center of gravity passes through the base (A). This unique alignment ensures that the gravitational force acting on the tower remains within its support base, preventing it from topplingRead more
The historical tower of Pisa does not fall even though it is tilted because the vertical line passing through its center of gravity passes through the base (A). This unique alignment ensures that the gravitational force acting on the tower remains within its support base, preventing it from toppling over. Despite its lean, the tower’s stable equilibrium is maintained because its center of gravity lies directly above its foundation. This architectural quirk has preserved the tower’s integrity for centuries, defying expectations and captivating visitors worldwide. Options (B) and (C) are incorrect because the tower’s stability is primarily due to its physical properties rather than divine intervention or a misalignment of its center of gravity. Option (D) is clearly not a valid explanation and merely dismisses the phenomenon as surprising without addressing its underlying mechanics. Therefore, the correct option is (A).
When it gets extremely cold during winter nights, water pipes burst because the volume of water increases after freezing (C). Water expands when it freezes, forming ice crystals that take up more space than liquid water. This expansion exerts tremendous pressure on the walls of the pipe, leading toRead more
When it gets extremely cold during winter nights, water pipes burst because the volume of water increases after freezing (C). Water expands when it freezes, forming ice crystals that take up more space than liquid water. This expansion exerts tremendous pressure on the walls of the pipe, leading to its rupture. Options (A), (B), and (D) are incorrect because they do not accurately explain the phenomenon of burst water pipes during freezing temperatures. The density of water decreases after freezing (A), but this doesn’t directly cause pipes to burst. Water becoming hard (B) doesn’t necessarily lead to pipe breakage, and the metal of water pipes doesn’t melt after freezing (D). The primary reason for burst pipes is the expansion of water upon freezing, which places excessive pressure on the pipe walls, ultimately causing them to rupture. Therefore, the correct option is (C).
A stoppered bottle filled with water will break when it freezes because the volume of water increases when it freezes (C). When water freezes, it expands, forming ice crystals that occupy more space than liquid water. This expansion exerts tremendous pressure on the walls of the bottle, causing it tRead more
A stoppered bottle filled with water will break when it freezes because the volume of water increases when it freezes (C). When water freezes, it expands, forming ice crystals that occupy more space than liquid water. This expansion exerts tremendous pressure on the walls of the bottle, causing it to rupture. Option (A) is incorrect because the bottle doesn’t shrink when the water freezes. Option (B) is also incorrect because the volume of water actually increases upon freezing, contrary to decreasing. Option (D) is irrelevant as the ability of glass to conduct heat doesn’t directly relate to the bottle breaking when water freezes. The primary reason for the bottle breaking is the expansion of water upon freezing, which exerts pressure on the bottle’s walls, ultimately causing it to rupture. Therefore, the correct option is (C).
When the temperature is dropped from 9°C to 3°C, the volume of water will first decrease and then increase (C). Water exhibits anomalous behavior near 4°C, where it contracts upon cooling until it reaches 4°C, then expands upon further cooling. Therefore, initially, as the temperature drops from 9°CRead more
When the temperature is dropped from 9°C to 3°C, the volume of water will first decrease and then increase (C). Water exhibits anomalous behavior near 4°C, where it contracts upon cooling until it reaches 4°C, then expands upon further cooling. Therefore, initially, as the temperature drops from 9°C to 4°C, the volume will decrease. However, upon further cooling from 4°C to 3°C, the volume will increase. Option (A) is incorrect because there is a change in volume due to the anomalous behavior of water near 4°C. Option (B) is incorrect because the volume does not consistently increase or decrease. Option (D) is incorrect because water does not necessarily freeze when the temperature drops from 9°C to 3°C; freezing occurs at 0°C or below. Therefore, the correct option is (C).
If we move from the equator towards the poles, the value of g
As we move from the equator towards the poles, the value of g decreases (B). This is due to the centrifugal force caused by Earth's rotation, which is greatest at the equator and decreases towards the poles. Additionally, the shape of the Earth is not a perfect sphere; it's slightly flattened at theRead more
As we move from the equator towards the poles, the value of g decreases (B). This is due to the centrifugal force caused by Earth’s rotation, which is greatest at the equator and decreases towards the poles. Additionally, the shape of the Earth is not a perfect sphere; it’s slightly flattened at the poles and bulging at the equator. This variation in distance from the Earth’s center also affects the gravitational force. As we move towards the poles, we are closer to the Earth’s center, resulting in a stronger gravitational force. However, this increase is offset by the decrease in centrifugal force, leading to a net decrease in the value of g. This decrease is not constant but varies gradually as we move from the equator towards the poles, reaching its maximum value at the poles. Therefore, the correct option is (B) decreases.
See lessBody weight is the
Body weight varies with location on Earth's surface due to differences in gravitational acceleration. It is not the same everywhere on Earth's surface. At the poles (B), gravity is stronger because objects are closer to the Earth's center. At the equator, the centrifugal force caused by Earth's rotaRead more
Body weight varies with location on Earth’s surface due to differences in gravitational acceleration. It is not the same everywhere on Earth’s surface. At the poles (B), gravity is stronger because objects are closer to the Earth’s center. At the equator, the centrifugal force caused by Earth’s rotation counteracts some of the gravitational force, resulting in slightly lower weight. Therefore, body weight is maximum at the poles and slightly lower at the equator. Additionally, weight can vary with altitude. On hills (D), the distance from the Earth’s center is slightly greater compared to plains, resulting in slightly lower weight. However, this difference is generally negligible unless at extreme altitudes. Thus, body weight is not the same everywhere, being maximum at the poles and slightly lower at the equator.
See lessAn astronaut can jump higher on the lunar surface than on the earth’s surface, because
An astronaut can jump higher on the lunar surface than on the Earth's surface because the force of gravity on the lunar surface is much less compared to the Earth's surface (C). This weaker gravity allows the astronaut to exert less downward force on the lunar surface, enabling them to achieve greatRead more
An astronaut can jump higher on the lunar surface than on the Earth’s surface because the force of gravity on the lunar surface is much less compared to the Earth’s surface (C). This weaker gravity allows the astronaut to exert less downward force on the lunar surface, enabling them to achieve greater height in their jump. While the astronaut is not weightless on the Moon (A), there is less gravitational pull due to the Moon’s smaller mass (D), but this difference primarily accounts for the discrepancy in weight, not the ability to jump higher. The absence of atmosphere on the Moon (B) does not significantly affect the astronaut’s ability to jump higher, as it primarily influences air resistance rather than gravitational force. Thus, the correct option is (C) The force of gravity on the lunar surface is very less as compared to the Earth’s surface.
See lessThe work done to hold a weight of 20 kg at a height of 1 m above the ground is
The work done to hold a weight of 20 kg at a height of 1 m above the ground is zero Joules (D). Work is defined as the product of force and displacement in the direction of the force. When holding an object stationary, like in this scenario, there is no displacement; thus, no work is done against grRead more
The work done to hold a weight of 20 kg at a height of 1 m above the ground is zero Joules (D). Work is defined as the product of force and displacement in the direction of the force. When holding an object stationary, like in this scenario, there is no displacement; thus, no work is done against gravity. While the weight of the object is 20 kg, and the force due to gravity is approximately 9.81 m/s² (981 N/kg), the vertical displacement is zero since the object is held at a constant height. Therefore, the work done is zero. Options (A), (B), and (C) are incorrect because they imply that work is being done, but in reality, no displacement occurs when holding the weight stationary at a constant height above the ground.
See lessIf a person pushes a wall but fails to displace it, then he does
If a person pushes a wall but fails to displace it, then he does no work (A). In physics, work is defined as the product of force and displacement in the direction of the force. When there is no displacement, regardless of the magnitude of the force applied, the work done is zero. Even though the peRead more
If a person pushes a wall but fails to displace it, then he does no work (A). In physics, work is defined as the product of force and displacement in the direction of the force. When there is no displacement, regardless of the magnitude of the force applied, the work done is zero. Even though the person exerts force against the wall, if the wall does not move, there is no change in the wall’s position, and hence no work is accomplished. Option (B) is incorrect because negative work implies that energy is being taken away from the system, which doesn’t apply here. Option (C) implies some positive work, but there’s no work done if there’s no displacement. Option (D) is incorrect because maximum work would imply achieving the greatest possible displacement, which isn’t the case if the wall remains stationary. Therefore, the correct option is (A) No work.
See lessA person climbing a hill leans forward because
A person climbing a hill leans forward to increase stability (D). Leaning forward shifts the center of mass towards the hillside, enhancing balance and reducing the risk of falling backward. This posture allows the individual to maintain a more stable foothold, minimizing the chance of slipping. AddRead more
A person climbing a hill leans forward to increase stability (D). Leaning forward shifts the center of mass towards the hillside, enhancing balance and reducing the risk of falling backward. This posture allows the individual to maintain a more stable foothold, minimizing the chance of slipping. Additionally, leaning forward enables better utilization of leg muscles, providing more power for propulsion uphill. It also reduces the strain on the back by distributing the load more evenly across the body. While leaning forward may contribute to a perception of increased speed, its primary purpose is to enhance stability and safety during the ascent. Therefore, the correct option is (D) to increase stability, as it aligns with the biomechanical advantages and safety considerations associated with leaning forward while climbing a hill.
See lessThe historical tower of Pisa does not fall even though it is tilted, because
The historical tower of Pisa does not fall even though it is tilted because the vertical line passing through its center of gravity passes through the base (A). This unique alignment ensures that the gravitational force acting on the tower remains within its support base, preventing it from topplingRead more
The historical tower of Pisa does not fall even though it is tilted because the vertical line passing through its center of gravity passes through the base (A). This unique alignment ensures that the gravitational force acting on the tower remains within its support base, preventing it from toppling over. Despite its lean, the tower’s stable equilibrium is maintained because its center of gravity lies directly above its foundation. This architectural quirk has preserved the tower’s integrity for centuries, defying expectations and captivating visitors worldwide. Options (B) and (C) are incorrect because the tower’s stability is primarily due to its physical properties rather than divine intervention or a misalignment of its center of gravity. Option (D) is clearly not a valid explanation and merely dismisses the phenomenon as surprising without addressing its underlying mechanics. Therefore, the correct option is (A).
See lessWhen it gets extremely cold during winter nights, water pipes burst because
When it gets extremely cold during winter nights, water pipes burst because the volume of water increases after freezing (C). Water expands when it freezes, forming ice crystals that take up more space than liquid water. This expansion exerts tremendous pressure on the walls of the pipe, leading toRead more
When it gets extremely cold during winter nights, water pipes burst because the volume of water increases after freezing (C). Water expands when it freezes, forming ice crystals that take up more space than liquid water. This expansion exerts tremendous pressure on the walls of the pipe, leading to its rupture. Options (A), (B), and (D) are incorrect because they do not accurately explain the phenomenon of burst water pipes during freezing temperatures. The density of water decreases after freezing (A), but this doesn’t directly cause pipes to burst. Water becoming hard (B) doesn’t necessarily lead to pipe breakage, and the metal of water pipes doesn’t melt after freezing (D). The primary reason for burst pipes is the expansion of water upon freezing, which places excessive pressure on the pipe walls, ultimately causing them to rupture. Therefore, the correct option is (C).
See lessA stoppered bottle filled with water will break when it freezes because
A stoppered bottle filled with water will break when it freezes because the volume of water increases when it freezes (C). When water freezes, it expands, forming ice crystals that occupy more space than liquid water. This expansion exerts tremendous pressure on the walls of the bottle, causing it tRead more
A stoppered bottle filled with water will break when it freezes because the volume of water increases when it freezes (C). When water freezes, it expands, forming ice crystals that occupy more space than liquid water. This expansion exerts tremendous pressure on the walls of the bottle, causing it to rupture. Option (A) is incorrect because the bottle doesn’t shrink when the water freezes. Option (B) is also incorrect because the volume of water actually increases upon freezing, contrary to decreasing. Option (D) is irrelevant as the ability of glass to conduct heat doesn’t directly relate to the bottle breaking when water freezes. The primary reason for the bottle breaking is the expansion of water upon freezing, which exerts pressure on the bottle’s walls, ultimately causing it to rupture. Therefore, the correct option is (C).
See lessWhat will be the change in volume of water if the temperature is dropped from 9 °C to 3 °C?
When the temperature is dropped from 9°C to 3°C, the volume of water will first decrease and then increase (C). Water exhibits anomalous behavior near 4°C, where it contracts upon cooling until it reaches 4°C, then expands upon further cooling. Therefore, initially, as the temperature drops from 9°CRead more
When the temperature is dropped from 9°C to 3°C, the volume of water will first decrease and then increase (C). Water exhibits anomalous behavior near 4°C, where it contracts upon cooling until it reaches 4°C, then expands upon further cooling. Therefore, initially, as the temperature drops from 9°C to 4°C, the volume will decrease. However, upon further cooling from 4°C to 3°C, the volume will increase. Option (A) is incorrect because there is a change in volume due to the anomalous behavior of water near 4°C. Option (B) is incorrect because the volume does not consistently increase or decrease. Option (D) is incorrect because water does not necessarily freeze when the temperature drops from 9°C to 3°C; freezing occurs at 0°C or below. Therefore, the correct option is (C).
See less