direct proportion

简明释义

正比例

英英释义

例句

1.The area of a rectangle is in direct proportion to its length and width.

矩形的面积与其长度和宽度成直接比例。

2.The cost of fuel is in direct proportion to the amount consumed.

燃料的费用与消耗量成直接比例。

3.As the temperature increases, the pressure of a gas is in direct proportion to its volume.

随着温度的升高，气体的压力与其体积成直接比例。

4.The distance you travel is in direct proportion to the speed at which you drive.

你行驶的距离与驾驶速度成直接比例。

5.In a recipe, the amount of ingredients needed is in direct proportion to the number of servings.

在食谱中，所需的成分数量与份数成直接比例。

作文

Understanding the concept of direct proportion is essential in both mathematics and real-life applications. When we say that two quantities are in direct proportion, it means that as one quantity increases, the other quantity also increases at a constant rate. Conversely, if one quantity decreases, the other also decreases. This relationship can be represented mathematically as y = kx, where k is a constant. This simple equation highlights the essence of direct proportion, illustrating that the ratio between the two variables remains constant. For example, consider a scenario involving distance and time. If a car travels at a constant speed, the distance covered is in direct proportion to the time spent traveling. If the car moves at a speed of 60 kilometers per hour, then in one hour, it will cover 60 kilometers. In two hours, it will cover 120 kilometers, and so on. Here, the distance (d) is directly proportional to the time (t), as d = 60t. The constant of proportionality (60 in this case) represents the speed of the car.In everyday life, we encounter direct proportion in many situations. For instance, when shopping for groceries, the cost of items is often in direct proportion to the quantity purchased. If one apple costs $1, then two apples will cost $2, three apples will cost $3, and so forth. This clear relationship allows consumers to easily calculate their expenses based on the number of items they wish to buy.Understanding direct proportion is not only limited to mathematical equations; it also extends to various fields such as physics, economics, and even cooking. In physics, the relationship between force and acceleration is a classic example of direct proportion. According to Newton's second law, force equals mass times acceleration (F = ma). If the mass remains constant, any increase in acceleration will result in a proportional increase in force. This principle helps us understand how different forces interact in the physical world.In economics, the concept of direct proportion can be seen in supply and demand. If the price of a product decreases, the quantity demanded typically increases, demonstrating a direct proportion between price and demand. This relationship is crucial for businesses when setting prices and forecasting sales. By understanding how these quantities interact, companies can make informed decisions to maximize their profits.Even in the kitchen, cooking often involves direct proportion. Recipes usually require specific ratios of ingredients. For example, if a recipe calls for 2 cups of flour for every cup of sugar, doubling the amount of sugar would necessitate doubling the amount of flour as well. This ensures that the final product has the desired taste and texture.In conclusion, the concept of direct proportion is a fundamental principle that permeates various aspects of our lives. From mathematics to everyday activities, recognizing and understanding this relationship enables us to make informed decisions and solve problems effectively. Whether we are calculating distances, budgeting for groceries, analyzing forces in physics, or following a recipe, the principle of direct proportion serves as a guiding framework. Mastering this concept not only enhances our mathematical skills but also enriches our understanding of the world around us.

理解直接比例的概念在数学和现实生活应用中至关重要。当我们说两个量是直接比例时，这意味着当一个量增加时，另一个量也以恒定的速率增加。相反，如果一个量减少，另一个量也会减少。这种关系可以用数学公式表示为y = kx，其中k是一个常数。这个简单的方程突出了直接比例的本质，说明两个变量之间的比例保持不变。例如，考虑一个涉及距离和时间的场景。如果一辆车以恒定的速度行驶，则所覆盖的距离与花费的时间成直接比例。如果汽车以每小时60公里的速度行驶，那么在一个小时内，它将覆盖60公里。在两个小时内，它将覆盖120公里，依此类推。在这里，距离(d)与时间(t)成直接比例，因为d = 60t。比例常数（在这种情况下为60）表示汽车的速度。在日常生活中，我们在许多情况下遇到直接比例。例如，在购买杂货时，物品的成本通常与购买数量成直接比例。如果一个苹果的价格是1美元，那么两个苹果将花费2美元，三个苹果将花费3美元，依此类推。这种明确的关系使消费者能够轻松根据他们希望购买的物品数量来计算开支。理解直接比例不仅限于数学方程；它还扩展到物理学、经济学甚至烹饪等多个领域。在物理学中，力与加速度之间的关系是直接比例的经典例子。根据牛顿第二定律，力等于质量乘以加速度（F = ma）。如果质量保持不变，加速度的任何增加将导致力的成比例增加。这个原理帮助我们理解不同力量在物理世界中的相互作用。在经济学中，直接比例的概念可以在供需中看到。如果一种产品的价格下降，需求量通常会增加，显示出价格与需求之间的直接比例关系。这种关系对于企业在设定价格和预测销售时至关重要。通过理解这些数量之间的相互作用，公司可以做出明智的决策，以最大化利润。即使在厨房中，烹饪也往往涉及直接比例。食谱通常需要特定的成分比例。例如，如果一个食谱要求每杯糖使用2杯面粉，那么如果糖的量翻倍，面粉的量也必须翻倍。这确保了最终产品具有所需的味道和质地。总之，直接比例的概念是一个基本原则，渗透到我们生活的各个方面。从数学到日常活动，识别和理解这种关系使我们能够做出明智的决策并有效解决问题。无论我们是在计算距离、预算杂货、分析物理中的力量，还是遵循食谱，直接比例的原则都作为指导框架。掌握这一概念不仅增强了我们的数学技能，还丰富了我们对周围世界的理解。