Objectives Compare and contrast independent and dependent variables. Section 1.2 Methods of Scientists Objectives Compare and contrast independent and dependent variables. Compare and contrast experimentation and investigation. Identify the differences between mass and weight.

Objectives Review Vocabulary Section 1.2 Methods of Scientists Objectives Explain what scientific notation is and how it is used. Review Vocabulary experiment: procedure performed in a controlled setting to test a hypothesis and collect precise data

Section 1.2 Methods of Scientists Scientists use scientific methods to structure their experiments and investigations. New Vocabulary scientific methods hypothesis independent variable dependent variable control Le Système International d’Unités (SI) scientific notation

The Nature of Scientific Investigations Section 1.2 Methods of Scientists The Nature of Scientific Investigations Scientists use similar methods to gather data and communicate information. Scientific methods are a series of problem-solving procedures that helps scientists conduct experiments.

The Nature of Scientific Investigations Section 1.2 Methods of Scientists The Nature of Scientific Investigations A hypothesis is a testable explanation of a situation that can be supported or disproved by careful procedures.

Visualizing Scientific Methods Section 1.2 Methods of Scientists Visualizing Scientific Methods Scientific methods are used by scientists to help organize and plan their experiments and investigations.

The Nature of Scientific Investigations Section 1.2 Methods of Scientists The Nature of Scientific Investigations Experimentation An experiment is classified as an organized procedure that involves making observations and measurements to test a hypothesis.

The Nature of Scientific Investigations Section 1.2 Methods of Scientists The Nature of Scientific Investigations The independent variable in an experiment is the factor that is changed by the experimenter. A dependent variable is a factor that is affected by changes in the independent variable.

The Nature of Scientific Investigations Section 1.2 Methods of Scientists The Nature of Scientific Investigations A control is used in an experiment to show that the results of an experiment are a result of the condition being tested.

The Nature of Scientific Investigations Section 1.2 Methods of Scientists The Nature of Scientific Investigations Investigation An investigation involves observation and collecting data but does not include a control.

The Nature of Scientific Investigations Section 1.2 Methods of Scientists The Nature of Scientific Investigations Analysis and conclusions During a scientific experiment, all data are carefully recorded. Once an experiment is complete, graphs, tables, and charts are commonly used to display data. These data are then analyzed so that a conclusion can be drawn.

The Nature of Scientific Investigations Section 1.2 Methods of Scientists The Nature of Scientific Investigations Analysis and conclusions Many times, a conclusion does not support the original hypothesis. In such a case, the hypothesis must be reevaluated and further research must be conducted.

Section 1.2 Methods of Scientists Measurement Le Système International d’Unités (SI) is a modern version of the metric system based on a decimal system. Length The SI unit for length is the meter (m).

Measurement Mass The amount of matter in an object is called mass. Section 1.2 Methods of Scientists Measurement Mass The amount of matter in an object is called mass. The SI unit of mass is the kilogram (kg).

Section 1.2 Methods of Scientists Measurement Weight Weight is a measure of the gravitational force on an object. The SI unit for force is the newton (N).

Measurement Area and volume Section 1.2 Methods of Scientists Measurement Area and volume Area is the amount of surface included within a set of boundaries. The SI unit for area is square meters (m2). Volume is the amount of space occupied by an object. The SI unit for volume is cubic meters (m3).

Section 1.2 Methods of Scientists Measurement Density Density is the measure of the amount of matter that occupies a given space. The SI units for density are expressed in grams per cubic centimeter (g/cm3), grams per milliliter (g/mL), and kilograms per cubic meter (kg/m3).

Measurement Time Time is the interval between two events. Section 1.2 Methods of Scientists Measurement Time Time is the interval between two events. The SI unit for time is the second (s). Temperature Temperature is a measure of the average kinetic energy of the particles that make up a material. The SI unit for temperature is the kelvin (K). Absolute zero is the coldest possible temperature.

Measurement Temperature Section 1.2 Methods of Scientists Measurement Temperature Temperature is a measure of the average kinetic energy of the particles that make up a material. The SI unit for temperature is the kelvin (K). Absolute zero is the coldest possible temperature.

Section 1.2 Methods of Scientists Scientific Notation In scientific notation, a number is expressed as a value between 1 and 10 multiplied by a power of 10.

Scientific Notation Example Section 1.2 Methods of Scientists Scientific Notation Example The number of grains of sand on Earth is approximately 4,000,000,000,000,000,000,000 and would be written as 4  1021.

Scientific Notation Example Section 1.2 Methods of Scientists Scientific Notation Example The mass of Earth at 5,974,200,000,000,000,000,000,000 kg would be written as 5.9742  1024 kg.

1 Study Guide Key Concepts Section 1.1 Earth Science Earth science encompasses five areas of study: astronomy, meteorology, geology, oceanography, and environmental science. Earth is divided into four systems: the geosphere, hydrosphere, atmosphere, and biosphere. Earth systems are all interdependent.

1 Study Guide Key Concepts Section 1.1 Earth Science Identifying the interrelationships between Earth systems leads to specialties and subspecialties. Technology is important, not only in science, but in everyday life. Earth science has contributed to the development of many items used in everyday life.

Section 1.2 Methods of Scientists Study Guide Key Concepts Section 1.2 Methods of Scientists Scientists use scientific methods to structure their experiments and investigations. Scientists work in many ways to gather data. A good scientific experiment includes an independent variable, dependent variable, and control. An investigation, however, does not include a control.

Section 1.2 Methods of Scientists Study Guide Key Concepts Section 1.2 Methods of Scientists Graphs, tables, and charts are three common ways to communicate data from an experiment. SI, a modern version of the metric system, is a standard form of measurement that all scientists use. To express very large or very small numbers, scientists use scientific notation.

1 The Nature of Science 1.2 Section Questions The number 1,280,000,000 can be written in scientific notation. Which answer choice is equal to this number? a. 1.28  107 b. 1.28  108 c. 1.28  109 d. 1.28  1010

1 The Nature of Science 1.2 Section Questions What term collectively refers to the problem-solving procedures that scientists use? a. experiments b. investigations c. hypotheses d. scientific methods

1 The Nature of Science 1.2 Section Questions A rock is broken into many pieces. Which of the following measures of the rock material increased as a result? a. mass b. weight c. area d. volume

Chapter Assessment Questions 1 The Nature of Science Chapter Assessment Questions Which of these examples best represents a scientific model? a. the salinity of typical ocean water b. the size and mass of the Moon c. a diagram of Earth’s interior d. a picture of a volcano on Mars

Chapter Assessment Questions 1 The Nature of Science Chapter Assessment Questions The Kelvin scale is often used to measure temperature during scientific experiments. Which value is the lowest possible temperature on this scale? a. 0 b. –100 c. –175 d. –273

Chapter Assessment Questions 1 The Nature of Science Chapter Assessment Questions Newton’s first law of motion is a scientific law. What do scientific laws provide to scientists? a. an explanation of why things occur b. a new idea that can be tested c. a description of how nature behaves d. an illustration or picture of nature

Chapter Assessment Questions 1 The Nature of Science Chapter Assessment Questions Le Système International d’Unités (SI) is the set of standard units that most scientists use for making measurements. In which unit should a person who is using the SI system express volume? a. the square foot (ft2) b. the square meter (m2) c. the cubic foot (ft3) d. the cubic meter (m3)

Chapter Assessment Questions 1 The Nature of Science Chapter Assessment Questions Why is scientific notation sometimes used when doing science? Answer: It is sometimes necessary when doing science to use numbers that are very large or very small. These numbers can be conveniently expressed by using scientific notation.

Standardized Test Practice 1 The Nature of Science Standardized Test Practice In a scientific experiment, which factor is changed or changes to produce the observed result? a. independent variable b. dependent variable c. constant d. control

Standardized Test Practice 1 The Nature of Science Standardized Test Practice An object is moved from Earth to the Moon. What measure of the object changes as a result? a. its weight b. its mass c. its volume d. its density

Standardized Test Practice 1 The Nature of Science Standardized Test Practice What requirement must all scientific hypotheses meet? a. They must be correct. b. They must be simple. c. They must be useful. d. They must be testable.

Standardized Test Practice 1 The Nature of Science Standardized Test Practice Which unit could be used to represent the density of an object? a. g/cm b. g/cm2 c. kg/m3 d. kg/m2

Standardized Test Practice 1 The Nature of Science Standardized Test Practice Why are scientific research reports often put through a process of peer review before they are published?

Standardized Test Practice 1 The Nature of Science Standardized Test Practice Answer: The peer review process helps the publisher select reports that make the most important contributions. It also helps reduce the number of mistakes and helps to ensure that the report’s conclusions are objective and fair.

1 The Nature of Science scientific methods hypothesis Section 1.2 Vocabulary scientific methods hypothesis independent variable dependent variable control Le Système International d’Unités (SI) scientific notation