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Introduction to Motion. ENGAGE. Journal Entry: All Motion Is Relative. Directions: Create and complete the following table in your science journal :. Understanding Motion. GOALS. Mission Objectives. Know how to accurately describe the position and/or motion of an object.
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Introduction to Motion ENGAGE Journal Entry: All Motion Is Relative Directions: Create and complete the following table in yourscience journal:
Understanding Motion GOALS Mission Objectives • Know how to accurately describe the position and/or motion of an object. • Explain what is meant when we say an object is in motion. • Explainthe difference between a scalar and a vector. • Recognizeand explain the difference between distance and displacement. • Useposition, speed, direction of motion, and a reference point to describe the motion of an object.
Understanding Motion Introduction So what IS motion anyway?!?! • In science,motionis the change of position of an object relative to a reference point. • A reference point is an object that appears to stay in place. • ANY object can be in motion or NOT in motion, depending on the reference point (perspective of the observer).
Understanding Motion Input Describing the Position of an Object • To accurately describe the position of an object, you must… • Establish a reference point. You usually need three(3) reference pointsto locate an object in 3 dimensional space! • Measure or estimate the distanceof the object from the reference point. • Describe the direction of the object’s location relative to the reference point. • Example:The moose is 0 cm above the goggles cabinet, 6 cm east of the west wall, and 30 cm south of the north wall.
Understanding Motion Input Describing the MOTION of an Object • When you describe the motion of an object, you should… • Establish a reference point. • Describe how the object’s distance is changing relative to the reference point (may include speed). • Describe the direction the object is moving in relative to the reference point.
Understanding Motion RECALL Journal Entry: Understanding Motion Write a paragraph that explains how you know when an object is in motion. You may draw diagrams to help make your explanation clear. Write your explanation in yourscience journal.
Understanding Motion: Practice • Fill in the Blank: A change in position with respect to a reference point is called _____________. • Describe the position of the digital clock on the classroom wall. • True/False: When standing still in a moving elevator, you are not moving from the reference point of the elevator. • If it is false, change the underlined word to make it true! • Explain your answer!!! • Describe the motion of a baseball that has just been pitched as seen from the reference point of home plate.
Describing Motion • Scalar: A measurement that involves a magnitude. (Magnitudeis an amountor quantityPLUS a unit!) • Examples: 20birds, 40grams, 65mph, 6meters. • Vector: A measurement that involves both a magnitude and a direction or position. • Examples: 65 mph NE; backing up 5 feet; 7,600 feetabove mean sea level.
REVIEW Journal Entry: Reviewing Relative Motion Respond to the following question in your science journal: You are sitting still in your seat on a bus that is traveling 100 km/h on a highway. Is your body at rest or in motion? Explain your answer! Use a diagram if it will help make your answer clear.
Describing Motion INPUT SPEED • Speed is the distance traveled divided by the time taken to travel that distance. It is a scalar quantity! • Speed is important in describing motion because it tells how fastan object is moving. • The units for speed are often m/s, but can be any distance unit divided by a time unit.
Guided Practice Describing Motion
Describing Motion INPUT Speed and Velocity: The same… but different! • Direction of Motion Speed and direction of motion are combined when describing an object’s velocity. • Velocity is a quantity that tells bothhow fastan object is moving (its speed) andits direction of motion relative to a reference point. • Velocity is a vectorquantity! • An object’s velocity may change even if its speed remains constant (by changing direction).
Check Understanding Describing Motion Draw a Venn Diagram comparing and contrasting Speed and Velocity
Describing Motion INPUT When velocity is a-changin’… • Sometimes the velocity of an object changes. The change in velocity over time is called acceleration. • Acceleration can be a change in speed, a change in direction, or both. • The most common units of acceleration are meters per second per second, which can be abbreviated m/s/s, but is usually written as m/s2.
Understanding Motion Examples
PRACTICE OldBluePhysical Science Textbook: Page 308 Problems: 2, 4, 5, 19 - 27.