1.
Thermal energy is the __________ of the particles in a material.
Correct Answer
B. Total energy
Explanation
Thermal energy refers to the total energy possessed by the particles in a material. It includes both the potential energy and the kinetic energy of the particles. Therefore, total energy is the correct answer to complete the sentence.
2.
Refrigerators use the process of __________ to remove heat from the interiors.
Correct Answer
D. Evaporation
Explanation
Refrigerators use the process of evaporation to remove heat from the interiors. Evaporation involves the conversion of a liquid into a gas, and in the case of refrigerators, a refrigerant liquid evaporates inside the evaporator coils. As the liquid evaporates, it absorbs heat from the surroundings, including the interior of the refrigerator, cooling it down. This process is essential for maintaining the low temperature inside the refrigerator and preserving the freshness of the stored food items.
3.
The moving particles in an object have __________ energy.
Correct Answer
C. Kinetic
Explanation
The correct answer is "kinetic" because kinetic energy is associated with the motion of particles. The particles in an object are in constant motion, and this motion contributes to the kinetic energy of the object. Therefore, the moving particles in an object have kinetic energy.
4.
If the particles in an object begin to move more quickly, their average kinetic energy __________ and the object's temperature __________.
Correct Answer
C. Increases, rises
Explanation
When the particles in an object begin to move more quickly, their average kinetic energy increases. This is because kinetic energy is directly proportional to the velocity of the particles. As the particles move faster, their kinetic energy increases. This increase in average kinetic energy leads to an increase in the object's temperature. Temperature is a measure of the average kinetic energy of the particles in an object. Therefore, as the particles move more quickly, the object's temperature also rises.
5.
The opposite of evaporation is __________.
Correct Answer
A. Condensation
Explanation
Evaporation is the process of converting a liquid into a gas, while condensation is the opposite process of converting a gas into a liquid. Therefore, the opposite of evaporation is condensation.
6.
__________ is the thermal energy that flows from a material with a higher temperature to one with a lower temperature.
Correct Answer
C. Heat
Explanation
Heat is the thermal energy that flows from a material with a higher temperature to one with a lower temperature. When there is a temperature difference between two objects, heat is transferred from the hotter object to the cooler object until both reach thermal equilibrium. This transfer of energy occurs through conduction, convection, or radiation. Heat is not the same as kinetic energy, work, or potential energy, as those are different forms of energy unrelated to temperature differences.
7.
According to Charles's law, at a constant pressure, if the temperature of a gas __________, the volume __________ .
Correct Answer
A. Increases; increases
Explanation
According to Charles's law, as the temperature of a gas increases, the volume of the gas also increases. This is because as the temperature increases, the gas molecules gain more energy and move faster, causing them to collide with each other and the walls of the container more frequently and with greater force. These increased collisions result in an increase in the volume of the gas.
8.
What causes a balloon to remain inflated?
Correct Answer
B. Air particles collide with the walls of the balloon.
Explanation
When air particles collide with the walls of the balloon, they exert pressure on the walls. This pressure is what keeps the balloon inflated. As long as the air particles continue to collide with the walls, the balloon will remain inflated. The other options mentioned, such as the temperature of the air inside the balloon decreasing or the walls of the balloon compressing the gas inside, do not explain why the balloon remains inflated. Additionally, the option of air particles continuing to enter through the balloon's walls does not explain why the balloon remains inflated, as it suggests that the balloon is being filled with more air particles rather than maintaining its current inflation.
9.
Which of the following best describes particles in a solid?
Correct Answer
D. Particles tightly packed together
Explanation
In a solid, particles are tightly packed together. This means that the particles are closely arranged and have limited movement. The strong intermolecular forces between the particles keep them in a fixed position, giving solids a definite shape and volume. Unlike liquids or gases, the particles in a solid do not slide past each other or fill the container they are in.
10.
The supporting force exerted by a fluid on an object immersed in it is called __________.
Correct Answer
C. Buoyant force
Explanation
When an object is immersed in a fluid, the fluid exerts an upward force on the object, which is known as the buoyant force. This force is exerted in the opposite direction to the force of gravity and is equal to the weight of the fluid displaced by the object. The buoyant force is what allows objects to float in fluids and is dependent on the density of the fluid and the volume of the object. Therefore, the correct answer is buoyant force.
11.
According to the kinetic theory, all matter is composed of __________.
Correct Answer
D. Particles
Explanation
According to the kinetic theory, all matter is composed of particles. This theory states that matter is made up of tiny particles that are constantly in motion. These particles can be atoms, molecules, or ions, depending on the type of matter. They have mass and occupy space, and their movement and interactions determine the physical properties of matter. Therefore, the correct answer is particles.
12.
According to Pascal, pressure applied to a fluid __________ .
Correct Answer
C. Is transmitted unchanged throughout the fluid
Explanation
According to Pascal, pressure applied to a fluid is transmitted unchanged throughout the fluid. This means that when pressure is applied to a fluid, it is evenly distributed and transmitted to all parts of the fluid without any change in magnitude. Pascal's principle states that any change in pressure applied to an enclosed fluid is transmitted undiminished to all portions of the fluid and to the walls of its container. This principle is the basis for various hydraulic systems and devices.
13.
According to Boyle's law, at a constant temperature, if the volume of a container of gas is __________, then pressure of the gas will __________ .
Correct Answer
D. Decreased; increase
Explanation
According to Boyle's law, at a constant temperature, if the volume of a container of gas is decreased, then the pressure of the gas will increase. This is because Boyle's law states that there is an inverse relationship between the volume and pressure of a gas. When the volume of the container decreases, the gas particles are forced into a smaller space, resulting in more frequent collisions with the container walls, leading to an increase in pressure.
14.
When the temperature of a substance is lowered, its particles __________ .
Correct Answer
A. Vibrate more slowly
Explanation
When the temperature of a substance is lowered, its particles vibrate more slowly. This is because temperature is a measure of the average kinetic energy of particles in a substance. As the temperature decreases, the particles have less energy and therefore vibrate at a slower rate.
15.
__________ is the ability of a fluid to exert an upward force on an object immersed in it.
Correct Answer
C. Buoyancy
Explanation
Buoyancy is the ability of a fluid to exert an upward force on an object immersed in it. This force is equal to the weight of the fluid displaced by the object. When an object is submerged in a fluid, it experiences an upward force due to the pressure difference between the top and bottom surfaces of the object. This force is called buoyant force and it is responsible for objects floating or sinking in fluids. The greater the buoyant force, the more likely the object is to float.