The room can be cooled effectively by releasing compressed gas. When compressed gas is released into a room, it undergoes expansion. This expansion process absorbs heat from the surrounding environment due to the endothermic nature of gas expansion, thereby cooling the air in the room. This principlRead more
The room can be cooled effectively by releasing compressed gas. When compressed gas is released into a room, it undergoes expansion. This expansion process absorbs heat from the surrounding environment due to the endothermic nature of gas expansion, thereby cooling the air in the room. This principle is the foundation of air conditioning and refrigeration systems. As the compressed gas expands, it absorbs thermal energy from the room’s air, resulting in a drop in temperature. The cooling effect is utilized in various cooling devices, such as air conditioners and refrigerators, where the refrigerant gas cycles through compression and expansion phases to maintain a cool environment. This method of cooling is efficient and widely used in residential, commercial, and industrial applications. Therefore, the correct answer is [B] by releasing compressed gas.
Running a fan in hot weather provides comfort primarily because it enhances the evaporation of sweat from our skin. When the air moves over the skin, it increases the rate at which sweat evaporates. This process, known as evaporative cooling, helps to cool the body as the phase change from liquid swRead more
Running a fan in hot weather provides comfort primarily because it enhances the evaporation of sweat from our skin. When the air moves over the skin, it increases the rate at which sweat evaporates. This process, known as evaporative cooling, helps to cool the body as the phase change from liquid sweat to vapor absorbs heat from the skin, lowering the body’s temperature. The fan does not produce cool air but rather circulates the existing air, making it feel cooler due to the increased evaporation rate. This effect is crucial for maintaining a comfortable body temperature in hot weather, as efficient evaporation is a key mechanism for heat regulation in humans. Therefore, the primary reason a fan provides comfort in hot weather is that our sweat evaporates faster, making the correct answer [B] Our sweat evaporates faster.
When salt is added to water, it affects the water's boiling and freezing points due to colligative properties. These properties depend on the number of solute particles in a solution, not their identity. The addition of salt (a solute) to water (the solvent) causes two significant changes: the boiliRead more
When salt is added to water, it affects the water’s boiling and freezing points due to colligative properties. These properties depend on the number of solute particles in a solution, not their identity. The addition of salt (a solute) to water (the solvent) causes two significant changes: the boiling point increases, and the freezing point decreases. This happens because the salt ions disrupt the formation of a solid lattice structure, making it harder for water to freeze, thus lowering the freezing point (a phenomenon known as freezing point depression). Simultaneously, the presence of salt raises the boiling point because it requires additional energy (heat) to break the interactions between the water molecules and the dissolved salt ions, leading to boiling point elevation. Therefore, the correct answer is [A] Boiling point increases and freezing point decreases.
The temperature of the Sun's surface, known as the photosphere, is approximately 6000K. The photosphere is the outer layer of the Sun that emits the light visible from Earth. This temperature is critical for understanding various solar phenomena, including the spectrum of light the Sun emits and itsRead more
The temperature of the Sun’s surface, known as the photosphere, is approximately 6000K. The photosphere is the outer layer of the Sun that emits the light visible from Earth. This temperature is critical for understanding various solar phenomena, including the spectrum of light the Sun emits and its interactions with Earth’s atmosphere. The photosphere’s temperature influences the color of the Sun, appearing as a bright, yellowish-white light due to its black-body radiation spectrum. Understanding this temperature helps astronomers study the Sun’s structure, energy output, and the processes driving solar activities such as sunspots and solar flares. Thus, the temperature of the Sun’s surface is best represented by the value 6000K, making the correct answer [C] 6000K.
The first law of thermodynamics, also known as the law of energy conservation, confirms the concept of energy conservation. This fundamental principle states that energy within an isolated system remains constant, implying that energy cannot be created or destroyed but can only change forms. For exaRead more
The first law of thermodynamics, also known as the law of energy conservation, confirms the concept of energy conservation. This fundamental principle states that energy within an isolated system remains constant, implying that energy cannot be created or destroyed but can only change forms. For example, during thermodynamic processes, energy can be transformed from heat to work or stored as internal energy within the system. The total energy input to a system, considering both heat and work, equals the change in the system’s internal energy. This law underpins the conservation of energy in all physical processes, providing a foundational framework for understanding energy transformations in various scientific and engineering contexts. It ensures that, regardless of the process, the total energy before and after remains the same. Thus, the first law of thermodynamics explicitly confirms the concept of energy conservation, making the correct answer [A] Energy conservation.
A thermostat in a refrigerator serves to maintain a consistent internal temperature. It operates by sensing the temperature inside the refrigerator and activating or deactivating the cooling mechanism as needed. When the internal temperature rises above a preset level, the thermostat signals the comRead more
A thermostat in a refrigerator serves to maintain a consistent internal temperature. It operates by sensing the temperature inside the refrigerator and activating or deactivating the cooling mechanism as needed. When the internal temperature rises above a preset level, the thermostat signals the compressor to start cooling. Conversely, when the temperature drops to the desired level, it turns off the compressor to prevent further cooling. This regulation ensures that the refrigerator maintains an optimal temperature for food preservation, preventing it from becoming too warm, which could spoil the food, or too cold, which could unnecessarily freeze items. By maintaining a steady temperature, the thermostat helps ensure energy efficiency and the effective functioning of the refrigerator. Therefore, the primary function of a thermostat in a refrigerator is to maintain the same temperature, making the correct answer [C] To maintain the same temperature.
In an isothermal change, a thermodynamic process occurs at a constant temperature. This means that the temperature of the system remains unchanged throughout the process. For this to happen, heat must be exchanged with the surroundings to compensate for any work done by or on the system. For exampleRead more
In an isothermal change, a thermodynamic process occurs at a constant temperature. This means that the temperature of the system remains unchanged throughout the process. For this to happen, heat must be exchanged with the surroundings to compensate for any work done by or on the system. For example, in an isothermal expansion, the system absorbs heat from the surroundings to maintain its temperature while doing work on the surroundings. Conversely, in an isothermal compression, the system releases heat to the surroundings as work is done on it. This type of process is often idealized in the study of gases, particularly in the context of the ideal gas law, where the product of pressure and volume remains constant if temperature is constant. Thus, in an isothermal change, the defining characteristic is that the temperature remains unchanged, making the correct answer [B] Temperature remains unchanged.
In an adiabatic change, a thermodynamic process occurs without any heat exchange between the system and its surroundings, meaning the heat remains unchanged. This is achieved by perfectly insulating the system. Despite no heat transfer, the temperature of the system can change as a result of work beRead more
In an adiabatic change, a thermodynamic process occurs without any heat exchange between the system and its surroundings, meaning the heat remains unchanged. This is achieved by perfectly insulating the system. Despite no heat transfer, the temperature of the system can change as a result of work being done on or by the system. For example, in an adiabatic expansion, the system does work on the surroundings, leading to a decrease in temperature, while in adiabatic compression, work is done on the system, causing an increase in temperature. This principle is crucial in understanding processes like the expansion of gases in engines or atmospheric phenomena. The conservation of energy still applies, but the energy change manifests solely as changes in internal energy, not heat transfer. Therefore, in an adiabatic change, the correct answer is [A] Heat remains unchanged.
The concept of internal energy is fundamentally derived from the first law of thermodynamics, which is also known as the law of energy conservation. This law states that energy cannot be created or destroyed, only transformed from one form to another within a closed system. Internal energy refers toRead more
The concept of internal energy is fundamentally derived from the first law of thermodynamics, which is also known as the law of energy conservation. This law states that energy cannot be created or destroyed, only transformed from one form to another within a closed system. Internal energy refers to the total energy contained within a system, encompassing both the kinetic energy of particles and the potential energy arising from intermolecular forces. The first law of thermodynamics provides a comprehensive framework for understanding how energy is stored, transferred, and conserved within a system. It articulates that the change in internal energy of a system is equal to the heat added to the system minus the work done by the system on its surroundings. This foundational principle is crucial for analyzing thermodynamic processes and systems in various scientific and engineering applications. Therefore, the correct answer is [B] First law.
The first law of thermodynamics, or the law of energy conservation, is fundamental in physics and thermodynamics. It asserts that the total energy in an isolated system remains constant. This means energy can neither be created nor destroyed; it can only change forms, such as from kinetic to potentiRead more
The first law of thermodynamics, or the law of energy conservation, is fundamental in physics and thermodynamics. It asserts that the total energy in an isolated system remains constant. This means energy can neither be created nor destroyed; it can only change forms, such as from kinetic to potential energy, or from chemical energy to thermal energy. The principle does not directly address momentum, which is conserved in a different context under Newton’s laws of motion. The conservation of energy applies universally across all processes, ensuring that the total energy before and after any transformation or transfer remains equal. This law underpins much of modern physics and engineering, dictating how energy systems are analyzed and designed. Thus, while momentum conservation is a crucial concept in its own right, it is the conservation of energy that is explicitly protected by the first law of thermodynamics. Therefore, the correct answer is [B] Energy.
The room can be cooled by
The room can be cooled effectively by releasing compressed gas. When compressed gas is released into a room, it undergoes expansion. This expansion process absorbs heat from the surrounding environment due to the endothermic nature of gas expansion, thereby cooling the air in the room. This principlRead more
The room can be cooled effectively by releasing compressed gas. When compressed gas is released into a room, it undergoes expansion. This expansion process absorbs heat from the surrounding environment due to the endothermic nature of gas expansion, thereby cooling the air in the room. This principle is the foundation of air conditioning and refrigeration systems. As the compressed gas expands, it absorbs thermal energy from the room’s air, resulting in a drop in temperature. The cooling effect is utilized in various cooling devices, such as air conditioners and refrigerators, where the refrigerant gas cycles through compression and expansion phases to maintain a cool environment. This method of cooling is efficient and widely used in residential, commercial, and industrial applications. Therefore, the correct answer is [B] by releasing compressed gas.
See lessRunning a fan in hot weather gives comfort because
Running a fan in hot weather provides comfort primarily because it enhances the evaporation of sweat from our skin. When the air moves over the skin, it increases the rate at which sweat evaporates. This process, known as evaporative cooling, helps to cool the body as the phase change from liquid swRead more
Running a fan in hot weather provides comfort primarily because it enhances the evaporation of sweat from our skin. When the air moves over the skin, it increases the rate at which sweat evaporates. This process, known as evaporative cooling, helps to cool the body as the phase change from liquid sweat to vapor absorbs heat from the skin, lowering the body’s temperature. The fan does not produce cool air but rather circulates the existing air, making it feel cooler due to the increased evaporation rate. This effect is crucial for maintaining a comfortable body temperature in hot weather, as efficient evaporation is a key mechanism for heat regulation in humans. Therefore, the primary reason a fan provides comfort in hot weather is that our sweat evaporates faster, making the correct answer [B] Our sweat evaporates faster.
See lessWhen salt is added to water, which of the following changes takes place?
When salt is added to water, it affects the water's boiling and freezing points due to colligative properties. These properties depend on the number of solute particles in a solution, not their identity. The addition of salt (a solute) to water (the solvent) causes two significant changes: the boiliRead more
When salt is added to water, it affects the water’s boiling and freezing points due to colligative properties. These properties depend on the number of solute particles in a solution, not their identity. The addition of salt (a solute) to water (the solvent) causes two significant changes: the boiling point increases, and the freezing point decreases. This happens because the salt ions disrupt the formation of a solid lattice structure, making it harder for water to freeze, thus lowering the freezing point (a phenomenon known as freezing point depression). Simultaneously, the presence of salt raises the boiling point because it requires additional energy (heat) to break the interactions between the water molecules and the dissolved salt ions, leading to boiling point elevation. Therefore, the correct answer is [A] Boiling point increases and freezing point decreases.
See lessThe temperature of the Sun’s surface is
The temperature of the Sun's surface, known as the photosphere, is approximately 6000K. The photosphere is the outer layer of the Sun that emits the light visible from Earth. This temperature is critical for understanding various solar phenomena, including the spectrum of light the Sun emits and itsRead more
The temperature of the Sun’s surface, known as the photosphere, is approximately 6000K. The photosphere is the outer layer of the Sun that emits the light visible from Earth. This temperature is critical for understanding various solar phenomena, including the spectrum of light the Sun emits and its interactions with Earth’s atmosphere. The photosphere’s temperature influences the color of the Sun, appearing as a bright, yellowish-white light due to its black-body radiation spectrum. Understanding this temperature helps astronomers study the Sun’s structure, energy output, and the processes driving solar activities such as sunspots and solar flares. Thus, the temperature of the Sun’s surface is best represented by the value 6000K, making the correct answer [C] 6000K.
See lessWhich concept does the first law of thermodynamics confirm?
The first law of thermodynamics, also known as the law of energy conservation, confirms the concept of energy conservation. This fundamental principle states that energy within an isolated system remains constant, implying that energy cannot be created or destroyed but can only change forms. For exaRead more
The first law of thermodynamics, also known as the law of energy conservation, confirms the concept of energy conservation. This fundamental principle states that energy within an isolated system remains constant, implying that energy cannot be created or destroyed but can only change forms. For example, during thermodynamic processes, energy can be transformed from heat to work or stored as internal energy within the system. The total energy input to a system, considering both heat and work, equals the change in the system’s internal energy. This law underpins the conservation of energy in all physical processes, providing a foundational framework for understanding energy transformations in various scientific and engineering contexts. It ensures that, regardless of the process, the total energy before and after remains the same. Thus, the first law of thermodynamics explicitly confirms the concept of energy conservation, making the correct answer [A] Energy conservation.
See lessThe function of thermostat in the refrigerator is
A thermostat in a refrigerator serves to maintain a consistent internal temperature. It operates by sensing the temperature inside the refrigerator and activating or deactivating the cooling mechanism as needed. When the internal temperature rises above a preset level, the thermostat signals the comRead more
A thermostat in a refrigerator serves to maintain a consistent internal temperature. It operates by sensing the temperature inside the refrigerator and activating or deactivating the cooling mechanism as needed. When the internal temperature rises above a preset level, the thermostat signals the compressor to start cooling. Conversely, when the temperature drops to the desired level, it turns off the compressor to prevent further cooling. This regulation ensures that the refrigerator maintains an optimal temperature for food preservation, preventing it from becoming too warm, which could spoil the food, or too cold, which could unnecessarily freeze items. By maintaining a steady temperature, the thermostat helps ensure energy efficiency and the effective functioning of the refrigerator. Therefore, the primary function of a thermostat in a refrigerator is to maintain the same temperature, making the correct answer [C] To maintain the same temperature.
See lessWhat happen in Isothermal Change?
In an isothermal change, a thermodynamic process occurs at a constant temperature. This means that the temperature of the system remains unchanged throughout the process. For this to happen, heat must be exchanged with the surroundings to compensate for any work done by or on the system. For exampleRead more
In an isothermal change, a thermodynamic process occurs at a constant temperature. This means that the temperature of the system remains unchanged throughout the process. For this to happen, heat must be exchanged with the surroundings to compensate for any work done by or on the system. For example, in an isothermal expansion, the system absorbs heat from the surroundings to maintain its temperature while doing work on the surroundings. Conversely, in an isothermal compression, the system releases heat to the surroundings as work is done on it. This type of process is often idealized in the study of gases, particularly in the context of the ideal gas law, where the product of pressure and volume remains constant if temperature is constant. Thus, in an isothermal change, the defining characteristic is that the temperature remains unchanged, making the correct answer [B] Temperature remains unchanged.
See lessWhat happen in Adiabatic Change
In an adiabatic change, a thermodynamic process occurs without any heat exchange between the system and its surroundings, meaning the heat remains unchanged. This is achieved by perfectly insulating the system. Despite no heat transfer, the temperature of the system can change as a result of work beRead more
In an adiabatic change, a thermodynamic process occurs without any heat exchange between the system and its surroundings, meaning the heat remains unchanged. This is achieved by perfectly insulating the system. Despite no heat transfer, the temperature of the system can change as a result of work being done on or by the system. For example, in an adiabatic expansion, the system does work on the surroundings, leading to a decrease in temperature, while in adiabatic compression, work is done on the system, causing an increase in temperature. This principle is crucial in understanding processes like the expansion of gases in engines or atmospheric phenomena. The conservation of energy still applies, but the energy change manifests solely as changes in internal energy, not heat transfer. Therefore, in an adiabatic change, the correct answer is [A] Heat remains unchanged.
See lessThe concept of internal energy is derived from which law of thermodynamics?
The concept of internal energy is fundamentally derived from the first law of thermodynamics, which is also known as the law of energy conservation. This law states that energy cannot be created or destroyed, only transformed from one form to another within a closed system. Internal energy refers toRead more
The concept of internal energy is fundamentally derived from the first law of thermodynamics, which is also known as the law of energy conservation. This law states that energy cannot be created or destroyed, only transformed from one form to another within a closed system. Internal energy refers to the total energy contained within a system, encompassing both the kinetic energy of particles and the potential energy arising from intermolecular forces. The first law of thermodynamics provides a comprehensive framework for understanding how energy is stored, transferred, and conserved within a system. It articulates that the change in internal energy of a system is equal to the heat added to the system minus the work done by the system on its surroundings. This foundational principle is crucial for analyzing thermodynamic processes and systems in various scientific and engineering applications. Therefore, the correct answer is [B] First law.
See lessThe first law of thermodynamics protects
The first law of thermodynamics, or the law of energy conservation, is fundamental in physics and thermodynamics. It asserts that the total energy in an isolated system remains constant. This means energy can neither be created nor destroyed; it can only change forms, such as from kinetic to potentiRead more
The first law of thermodynamics, or the law of energy conservation, is fundamental in physics and thermodynamics. It asserts that the total energy in an isolated system remains constant. This means energy can neither be created nor destroyed; it can only change forms, such as from kinetic to potential energy, or from chemical energy to thermal energy. The principle does not directly address momentum, which is conserved in a different context under Newton’s laws of motion. The conservation of energy applies universally across all processes, ensuring that the total energy before and after any transformation or transfer remains equal. This law underpins much of modern physics and engineering, dictating how energy systems are analyzed and designed. Thus, while momentum conservation is a crucial concept in its own right, it is the conservation of energy that is explicitly protected by the first law of thermodynamics. Therefore, the correct answer is [B] Energy.
See less