Section outline

  • General

    Collapse all Expand all

  • 质量或容量的适当公制单位

    lesson content

    ::[图1]

    Jesse works in the mailroom of a large company. Part of his responsibility is to make sure all mail is sent out with the correct postage. The postage depends on the size and weight of the mail. He is given a box that contains 10 books and some documents. Which metric unit of measurement should Jesse use to weight the package?
    ::Jesse在一家大公司的收发室工作,他的部分职责是确保所有邮件都以正确的邮资寄出。邮资取决于邮件的大小和重量。给他一个盒子,里面有10本书和一些文件。Jesse应该用哪个计量单位来加权包裹?


    In this concept, you will learn to choose the appropriate metric unit of mass or  capacity  for the situation.
    ::在这一概念中,你将学会选择适合情况的适当质量或能力衡量单位。

    Metric Units for Mass or Capacity
    ::质量或容量计量单位

    Grams, milligrams, and kilograms are metric units for measuring mass. To really understand each unit, you have to understand the size of each unit. Here are some examples of things that might weigh 1 of each metric unit of mass.
    ::克、 毫克和公斤是测量质量的度量单位。 要真正理解每个单位, 您必须了解每个单位的大小 。 下面是每公吨重量中可能重1个的示例 。

    Unit Examples
    1 kilogram 1 liter of water, dictionary
    1 gram paperclip, one dollar bill
    1 milligram a grain of sand, ant

    It would be best to measure heavier objects like people or textbooks in kilograms. Grams are often used to measure ingredients in baking recipes. Milligrams are very tiny units that are not used very often in everyday situation. Scientists are one group of people that might use milligrams to measure objects with very little mass.
    ::最好是测量比重更重的物体,如人或教科书的公斤数。 在烘烤食谱中,克数常常用来测量成分。 毫克是很小的单位,在日常生活中很少使用。 科学家是可能会使用毫克测量质量极小的物体的一组人。

    Liters and milliliters are metric units for measuring capacity. Here are some examples of things that might weigh 1 of each metric unit of capacity.
    ::公升和毫升是衡量容量的计量单位,这里是每公吨容量中重量1个的一些例子。

    Unit Examples
    1 liter 1 liter of water,  quart  of milk
    1 milliliter 20 drops, one-fifth of 1 teaspoon

    A liter would be used to measure much larger volumes of liquid, like the capacity of a car’s fuel tank. Millimeters are much smaller and would be used to measure very small amounts of liquid, like the amount of cough syrup you should take.
    ::升能将被用于测量更大量的液体,比如汽车燃料箱的容量。 毫米要小得多,用来测量很小量的液体,比如你应该服用的咳嗽糖浆。

    Think carefully about what is being measured before you decide on which unit to use.
    ::在决定使用哪个单位之前,请仔细考虑正在衡量的单位。

    Examples
    ::实例

    Example 1
    ::例1

    Earlier, you were given a problem about Jesse in the mailroom.
    ::早些时候,有人在收发室里 给了你Jesse一个问题

    Jesse needs to decide which metric unit he should use to weigh a box of books and documents.
    ::Jesse需要决定 他应该用哪个计量单位 来权衡一箱书和文件

    First, think about the size and weight of the objects in the box.
    ::首先,想想盒子里物体的大小和重量。

    Milligrams would be far too small of a unit. The books alone would probably weigh a few million milligrams. Even grams is really not ideal, since the total weight would be thousands of grams.
    ::单是书本就可能有几百万毫克的重量。 即使是克也并不理想,因为总重量是数千克。

    Jesse should use kilograms to weigh the package for postage.
    ::Jesse应该用公斤来权衡邮包的重量

    Example 2
    ::例2

    Choose the best unit of measurement.
    ::选择最好的计量单位。

    Which unit of mass would you use to measure a handful of peanuts?
    ::你用哪个质量单位来测量一小撮花生?

    First, think about the size and weight of a handful of peanuts and then choose the best unit for measuring mass.
    ::首先,想想一小撮花生的大小和重量 然后选择测量质量的最佳单位

    Peanuts are small, so the kilogram would be too much for a handful of peanuts. Peanuts may be small, but they are much larger than grains of sand. Milligrams would be too small to measure peanuts.
    ::花生是小的,因此对于一小撮花生来说,这公斤是太大的。 花生可能很小,但比沙粒大得多。 花生太小,无法测量花生。

    Grams would be the best unit to weigh a handful of peanuts.
    ::格拉姆是称一小撮花生的最好的单位

    Example 3
    ::例3

    Choose the best unit of measurement: the weight of 5 pennies.
    ::选择最好的计量单位:5便士的重量。

    First, think about the size and weight of 5 pennies and then choose the best unit for measuring mass.
    ::首先,想想5便士的大小和重量 然后选择测量质量的最佳单位

    5 pennies would definitely weigh less than a kilogram and be too heavy for milligrams.
    ::5便士的重量肯定低于1公斤, 并且太重,不适合毫克。

    Grams would be the best unit to weigh 5 pennies, since each penny is about 2.5 grams.
    ::因为每分约2.5克。

    Example 4
    ::例4

    Choose the best unit of measurement: the amount of water in a bathtub.
    ::选择最好的测量单位:浴缸的水量。

    First, think about the size of a bathtub and choose the best unit for measuring capacity.
    ::首先,想想浴缸的大小 选择最好的测量单位

    Milliliters would be far too small to measure the amount of water a bathtub can hold.
    ::米利特人太小了 无法测量浴缸能容纳的水量

    Liters would be the better unit of capacity for the amount of water in a bathtub.
    ::在浴缸的水量方面,上衣将是一个更好的能力单位。

    Example 5
    ::例5

    Choose the best unit of measurement: the weight of a car.
    ::选择最佳计量单位:汽车重量。

    First, think about the size and weight of a car and then choose the best unit for measuring mass.
    ::首先,考虑汽车的大小和重量,然后选择测量质量的最佳单位。

    A car is large and very heavy, so you will need the largest unit of the three choices.
    ::一辆大而重的汽车, 所以你需要三个选择中最大的一个单位。

    Kilograms would be the best unit to weigh a car of the three.
    ::公斤是三辆车中 最能称重的单位

    Review
    ::回顾

    Choose the best metric unit of either mass or capacity to measure each item.
    ::选择质量或测量每个物品的能力的最佳度量单位。

    1. A dictionary
      ::词典
    2. A flea under a microscope
      ::显微镜下的跳蚤
    3. A jug of apple cider
      ::一壶苹果苹果汁
    4. An almond
      ::杏仁
    5. Drops of water from an eyedropper
      ::眼水滴的水滴,
    6. Ten dimes
      ::10 美圆
    7. A bucket of water
      ::一桶水
    8. A baby bottle
      ::婴儿瓶子
    9. A handful of rice
      ::几米米饭
    10. A large jug of water
      ::一大壶水
    11. A water tower
      ::水塔
    12. The water in a swimming pool
      ::游泳池的水
    13. The weight of a boat
      ::船的重量 船的重量
    14. A handful of sand
      ::一小片沙沙
    15. The weight of a backpack
      ::背包重量

    Review (Answers) 
    ::回顾(答复)

    Click   to see the answer key or go to the Table of Contents and click on the Answer Key under the 'Other Versions' option.
    ::单击可查看答题键, 或转到目录中, 单击“ 其他版本” 选项下的答题键 。

    Resources
    ::资源