Barometer

A barometer is a scientific instrument used to measure atmospheric pressure. It is commonly used in weather forecasting and for determining altitude. There are two main types of barometers: mercury barometers and aneroid barometers.

Mercury Barometer

A mercury barometer consists of a long glass tube filled with mercury, which is inverted into a container of mercury. The height of the mercury column in the tube is a measure of the atmospheric pressure. As the atmospheric pressure changes, the height of the mercury column will rise or fall accordingly.

Aneroid Barometer

An aneroid barometer uses a small, flexible metal box called an aneroid cell. This cell is made from an alloy of beryllium and copper. As the atmospheric pressure changes, the cell expands or contracts, causing a needle on the barometer to move and indicate the pressure.

Units of Measurement

The standard unit of measurement for atmospheric pressure is the bar. However, pressure is often measured in millibars (mb) or inches of mercury (inHg) in the United States.

Study Guide

What is a barometer used for?
Explain the difference between a mercury barometer and aneroid barometer.
What are the units of measurement for atmospheric pressure?
How does an aneroid barometer work?
Why is it important to measure atmospheric pressure?

Understanding the concept of a barometer and how it works is important for various scientific fields, especially meteorology and aviation. I hope this study guide helps you understand the topic better!

◂Math Worksheets and Study Guides Eighth Grade. Displaying data

Organizing & Displaying Data

The resources above cover the following skills:

Data Analysis and Probability (NCTM)

Formulate questions that can be addressed with data and collect, organize, and display relevant data to answer them.

Select, create, and use appropriate graphical representations of data, including histograms, box plots, and scatterplots.

Select and use appropriate statistical methods to analyze data.

Discuss and understand the correspondence between data sets and their graphical representations, especially histograms, stem-and-leaf plots, box plots, and scatterplots.

Develop and evaluate inferences and predictions that are based on data.

Make conjectures about possible relationships between two characteristics of a sample on the basis of scatterplots of the data and approximate lines of fit.

Grade 8 Curriculum Focal Points (NCTM)

Data Analysis and Number and Operations and Algebra: Analyzing and summarizing data sets

Students use descriptive statistics, including mean, median, and range, to summarize and compare data sets, and they organize and display data to pose and answer questions. They compare the information provided by the mean and the median and investigate the different effects that changes in data values have on these measures of center. They understand that a measure of center alone does not thoroughly describe a data set because very different data sets can share the same measure of center. Students select the mean or the median as the appropriate measure of center for a given purpose.

Connections to the Grade 8 Focal Points (NCTM)

Data Analysis: Building on their work in previous grades to organize and display data to pose and answer questions, students now see numerical data as an aggregate, which they can often summarize with one or several numbers. In addition to the median, students determine the 25th and 75th percentiles (1st and 3rd quartiles) to obtain information about the spread of data. They may use box-and-whisker plots to convey this information. Students make scatterplots to display bivariate data, and they informally estimate lines of best fit to make and test conjectures.