- Slides: 31
HOW FAR? DISTANCE AND DISPLACEMENT JAN 10 – JAN 17 Physical Science
DO NOW (WORTH TRIBAL POINTS) Grab a Calculator!!!!!!! Be quiet and working when the bell rings (30 tribal points) Explain how you can tell if an object is moving? § Use complete sentences to explain yourself.
WHAT IS MOTION? In science, motion is the change in position for a particular time interval. To describe motion accurately, a frame of reference is needed.
WHAT IS A FRAME OF REFERENCE? § The background or object that is stationary, and is used for comparing different positions of an object. § The frame of reference depends on the type of motion and the position of the OBSERVER.
WHICH OBJECT WOULD BE THE FRAME OF REFERENCE. . . THE TREE OR CAR?
WHICH OBJECT WOULD BE THE FRAME OF REFERENCE. . . THE TRUCK OR MAN?
WHICH OBJECT WOULD BE THE FRAME OF REFERENCE. . . THE EARTH OR SATELLITE?
WHAT IS THE DIFFERENCE BETWEEN DISTANCE AND DISPLACEMENT? DISTANCE Is a SCALAR DISPLACEMENT Is a VECTOR quantity (only magnitude) quantity (both magnitude and direction § Example Units for scalar quantities: § 5 meters § 10 kilometers § 12 miles § Example units for vector quantities: § 10 km East § 5 m North of East § 100 km West
WHAT IS THE DIFFERENCE BETWEEN DISTANCE AND DISPLACEMENT? DISTANCE Length the object travelled. DISPLACEMENT Length of the path an object moves in a particular direction.
HOW TO SOLVE FOR DISTANCE AND DISPLACEMENT…
Displacement vs Distance PROBLEM #1 a What is the total distance travelled by Tim if he takes the path ABC?
Distance 4 m + 3 m = 7 m
PROBLEM #1 b What is the total displacement travelled by Tim (AC)? Pythagorean theorem
Pythagorean theorem § Applied to Triangles TRIBAL POINTS Try and solve for C
SOLVE FOR DISPLACEMENT…
INDIVIDUAL CHALLENGE Solve for the displacement of the ball rolling down the hill. 5 x 10
What if the object does not travel in a triangular motion? Tribal Challenge: Discuss
A bird flies 5 meters North, then 7 meters South. § What is the total DISTANCE travelled by the bird? PROBLEM #2 a Tribal Challenge (20 pts)
§ When solving for displacement, if the object doesn’t travel in a triangular motion, use the following arrows to symbolize the direction: §↑ North §↓ South §→East §← West
A bird flies 5 meters North, then 7 meters South. § What is the total DISPLACEMENT travelled by the bird? § ↑ 5 m - ↓ 7 m = ↓ 2 m § You will subtract because the directions are opposite. § The direction of the arrow in the answer should be the direction of the arrow with the largest number. PROBLEM #2 b
Try these!!! A little boy plays with a toy car he moves it East 50 cm and West 50 cm. What is the total distance traveled and displacement of the toy car? I throw a ball in the air. It goes up in the air 10 m but gets stuck in a tree and never comes down . What is the distance and displacement of the ball? INDIVIDUAL CHALLENGE
MORE PRACTICE WITH DISPLACEMENT AND DISTANCE… A delivery truck travels: § 18 blocks North ↑ § 10 blocks West ← § 16 blocks South ↓ What is the distance and displacement of the truck from its starting point? Assume the blocks are equal length.
DISTANCE… A delivery truck travels: § 18 blocks North ↑ § 10 blocks West ← § 16 blocks South ↓ § Distance: § 18 blocks + 10 blocks + 16 blocks = Distance = 44 blocks
DISPLACEMENT… Draw it out!!!!! A delivery truck travels: § 18 blocks North ↑ § 10 blocks West ← § 16 blocks South ↓
SOLVE FOR DISTANCE AND DISPLACEMENT… Jim Nazium is walking from lunch to his PE class. He leaves the lunchroom and walks 43 m west. He then turns and walks 72 m north down the hallway leading to the locker room. Determine the distance and displacement of Jim. Draw a picture to help you solve the problem.
SOLVE FOR DISTANCE AND DISPLACEMENT… 43 m West 72 m North Distance: 43 m + 72 m = 115 m
SOLVE FOR DISTANCE AND DISPLACEMENT… On her trip from home to school, Karla drives along three streets after pulling out the driveway. She drives 1. 85 miles south, 2. 43 miles east and 0. 35 miles north. Determine Karla's distance and displacement.
SOLVE FOR DISTANCE AND DISPLACEMENT…
SOLVE FOR DISTANCE AND DISPLACEMENT…TRIBAL CHALLENGE (60 PTS) Sheila is captain of the Varsity cross country team. During the afterschool practice on Tuesday, she led the team on the following run from school to a nearby park where they met the coach for a meeting: 0. 68 miles, north; 1. 09 miles east; 1. 56 miles north; 0. 32 miles, west. Determine the distance and displacement of the team.
SOLVE FOR DISTANCE AND DISPLACEMENT…