ONE DIMENSIONAL MOTION 1. Give pairs of students post it notes and a marker. On the board draw two columns, label the one on the left fundamental (basic) and the one on the right derived (combination). In the column on the left write the letters of the alphabet. Ask students (as pairs or individuals) to create a word using any combination of the letters on the board. You could stop at 1 word per pair of students or give the class 1 minute to create as many words as possible. Ask, “how many words can be created from these 26 letters?” (unlimited) In science, we use the metric system ONE DIMENSIONAL MOTION

What is a Measurement? A measurement is a comparison between an unknown quantity and a standard. Measurements quantify observations. Careful measurements enable you to derive the relation between any two quantities. 1. Ask students to write the definition of quantify.

Section 1.1 SI Units The Système International d’Unités, or SI, uses seven base quantities, which are shown in the table below. My students are required to know these units and their abbreviations by heart.

Section 1.1 Fundamental Units SI Units The base quantities were originally defined in terms of direct measurements. Quantities such as length can be measured with a meter stick. All of these quantities can be measured directly in a high school science lab.

The standard for length The distance traveled by light in a vacuum in 1/299,792,458 of a second. The standard for length used to be a fraction of the distance from the north pole to the equator. I don’t require students to know this.

1-2 Units of Length Examples of length

The standard for time… One second is the time for radiation from a cesium-133 atom to complete 9,192,631,770 oscillation cycles. Student enrichment and FYI

1-2 Units of Time More examples of time

The standard for mass is… One kilogram is the mass of a particular platinum-iridium cylinder kept at the International Bureau of Weights and Standards, Sèvres, France. Student enrichment and FYI

1-2 Units of Mass Briefly touch on examples of mass

Derived Units Other units, called derived units, are created by combining the base units in various ways. Just as with the post-it note activity, get students to make the connection between fundamental and derived units. Fundamental units are like the letters of the alphabet, and derived units are the equivalent of words.

An example of a derived unit In the metric system force is measured in Newtons 1Newton = 1 kg m/s2 What does this quarter pounder with cheese have to do with the Newton?! Here’s cool way to remember the newton. (1 Newton = ¼ pound)

Derived Unit Example (cont) In the metric system the unit of energy is the Joule (pronounced JOOL). 1 Joule = 1 kg m2/s2 Another way to remember the unit for energy.

Mathematics and Physics Prefixes are used to change SI units by powers of 10, as shown in the table below. SI Units How cool is the metric system. Conversions within the metric system are very easy compared to the English system. In metrics changing units is a matter of changing powers of ten.

Scalar vs. Vector Quantity Simply states the amount or “how much” Ex: 1 meter (distance) 1 meter/second (speed) States both the quantity and the direction Ex: -1 meter (displacement) -1 meter/second (velocity)

How is motion represented? Lesson Objectives: Draw motion diagrams to describe motion Develop a particle model to represent a moving object List and define the 3 types of motion

KINEMATICS IN ONE DIMENSION The study of motion along one axis without rotation. Are there different types of motion? Kinematics is the study of how things move. In section we will begin to take an oversimplified look at how objects, regardless of shape and mass, move.

Motion Diagrams (How is motion visualized) An easy way to study motion is to make a “movie” of a moving object. A motion diagram represents an object’s motion at several instants of time. An easy way to study motion is to make a “movie” of a moving object. A motion diagram represents an object’s motion at several instants of time

An easy way to study the motion is to record a video of a moving object. A video camera takes images at a fixed rate, usually 30 images every second. Each separate image is called a frame. Imagine that you set the camera on a tripod and recorded the motion as the object passed by without panning. If we exam each frame separately, we see that the car is iin different positions.

“Layering” frames of the car’s motion… Let’s pretend that we edited the video from the previous slide by layering frames on top of each other, the final result is the motion diagram featured in this slide. A motion diagram of the car shows all the frames simultaneously

Describe this skateboarder’s motion. Images that are equally spaced indicate an object moving with constant speed. Describe this skateboarder’s motion.

Describe this runner’s motion This runner is speeding up. How can you tell? ( An increasing distance between the images shows the object is speeding up) Describe this runner’s motion

Describe the motion of this car? This car is slowing down. How can you tell? ( A decreasing distance between the image shows the object is slowing down) Describe the motion of this car?

Motion Diagrams (How is motion visualized) By Definition… A motion diagram represents an object’s motion at several instants of time. An easy way to study motion is to make a “movie” of a moving object. A motion diagram represents an object’s motion at several instants of time

Which car is going faster, 1 or 2 Which car is going faster, 1 or 2? Assume there are equal intervals of time between the frames of both movies. Car 1 Car 2 (2)The images of 2 are further apart so it travels a larger distance than does 1 during the same time interval.

Which car is going faster, 1 or 2 Which car is going faster, 1 or 2? Assume there are equal intervals of time between the frames of both movies. Car 1 Car 2 2 is going faster

Particle Model A simplification in which we treat a moving object as if all of its mass were concentrated at a single point.

Since models are over simplifications, the size, shape and type of car is irrelevant here. The motion diagram below it shows the car as a particle. Ask students to describe the car’s motion.

2. (a) is ball, (b) is dust, (c) is rocket Three motion diagrams are shown. Which is a dust particle settling to the floor at constant speed, which is a ball dropped from the roof of a building, and which is a descending rocket slowing to make a soft landing on Mars? 1. (a) is dust, (b) is ball, (c) is rocket 2. (a) is ball, (b) is dust, (c) is rocket 3. (a) is rocket, (b) is dust, (c) is ball 4. (a) is rocket, (b) is ball, (c) is dust 5. (a) is ball, (b) is rocket, (c) is dust The correct answer is (2) Dropped ball Dust particle Descending rocket

2. (a) is ball, (b) is dust, (c) is rocket Three motion diagrams are shown. Which is a dust particle settling to the floor at constant speed, which is a ball dropped from the roof of a building, and which is a descending rocket slowing to make a soft landing on Mars? 1. (a) is dust, (b) is ball, (c) is rocket 2. (a) is ball, (b) is dust, (c) is rocket 3. (a) is rocket, (b) is dust, (c) is ball 4. (a) is rocket, (b) is ball, (c) is dust 5. (a) is ball, (b) is rocket, (c) is dust STT1.2

Questions????