Q: What is the name for speed with a direction? Read this paragraph and choose the correct option from the provided answers: Speed represents how quickly an object is moving through space. Velocity is speed with a direction, making it a vector quantity. If an object's velocity changes with time, the object is said to be accelerating. As we'll see in the next chapters, understanding the acceleration of an object is the key to understanding its motion. We will assume constant acceleration throughout this chapter. Choices: - distance - acceleration - trajectory - velocity A:
velocity
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Q: Convection is the transfer of thermal energy by particles moving through what? Read this paragraph and choose the correct option from the provided answers: Convection is the transfer of thermal energy by particles moving through a fluid. Particles transfer energy by moving from warmer to cooler areas. That's how energy is transferred in the soup in Figure above . Particles of soup near the bottom of the pot get hot first. They have more energy so they spread out and become less dense. With lower density, these particles rise to the top of the pot (see Figure below ). By the time they reach the top of the pot they have cooled off. They have less energy to move apart, so they become denser. With greater density, the particles sink to the bottom of the pot, and the cycle repeats. This loop of moving particles is called a convection current . Choices: - Solid - tissue - Metal - fluid A:
fluid
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Q: Unlike wood and glass, steel is an example of a material that responds to what force? Read this paragraph and choose the correct option from the provided answers: Magnetism is the ability of a material to be attracted by a magnet and to act as a magnet. No doubt you've handled refrigerator magnets like the ones in Figure below . You probably know first-hand that they stick to a metal refrigerator but not to surfaces such as wooden doors and glass windows. Wood and glass aren't attracted to a magnet, whereas the steel refrigerator is. Obviously, only certain materials respond to magnetic force. Choices: - kinetic - electromagnetic - thermal - magnetic A:
magnetic
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Q: What is defined as a repeating series of events that include growth, dna synthesis, and cell division? Read this paragraph and choose the correct option from the provided answers: Cell division is just one of several stages that a cell goes through during its lifetime. The cell cycle is a repeating series of events that include growth, DNA synthesis, and cell division. The cell cycle in prokaryotes is quite simple: the cell grows, its DNA replicates, and the cell divides. In eukaryotes, the cell cycle is more complicated. Choices: - photosynthesis - meiosis - puberty - cell cycle A:
cell cycle
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