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).
A 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).
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