Motion

Describing Position A reference point is an object you choose to describe the location/position of another object For example: If I wanted to describe the location of the flower pot, what could I use as the reference point?

Describing Position A position is an object’s distance and direction from a reference point For example: point A is 25 miles NW of point B

Describing Position You can describe position by using NORTH, SOUTH, EAST, or WEST directions

= 1 mile From the start, go NORTH 4 miles. Where are you now? Go 3 miles EAST. Where are you now? Go 3 miles SOUTH. Where are you now? Go 4 miles WEST. Where are you now? Go 5 miles NORTH. Where are you? Go 3 miles SOUTH then 2 miles WEST. Where are you? Go 3miles SOUTH. Where are you? Go 4 miles EAST, 2 miles NORTH, then 3 miles WEST. Where are you? Letter box Newsagents Police station Bank Book shop Fire station Bus stop School

Discussion Questions 10 points each

Motion – the process of changing position Motion is based off of a reference point

Speed can be constant or changing Speed – a measure of how fast the object gets from one place to another Speed can be constant or changing Most of the time objects do not travel at a constant speed. So speed is determined by using an average speed.

Average speed – is the total distance traveled divided by the total time taken to travel that distance Most of the time objects do not travel at a constant speed. So speed is determined by using an average speed.

Most of the time objects do not travel at a constant speed Most of the time objects do not travel at a constant speed. So speed is determined by using an average speed.

What is the average speed of a student who ran a 200 meter track in 120 seconds? 1.6 m/s

What is the speed of a train that goes 1,000 km in 5 hours? 200 km/h

If the average speed of a car is 110 km/h, how long will it take the car to travel 715 km? S= d/t 110 km/h = 715 km/ ? ? = 6.5h

If it takes a baseball player 2 If it takes a baseball player 2.5 seconds to run from the batters box to first base at an average speed of 6.5 meters per second, what is the distance she covers in that time? 16.3 m

Velocity – the speed of an object in a particular direction An airplanes velocity is 600 km/h An airplanes velocity is 600 km/h south SPEED IS NOT VELOCITY AND VELOCITY IS NOT SPEED

an object’s velocity changes if either its speed or direction changes Changing Velocity an object’s velocity changes if either its speed or direction changes if a car slows down or speeds up its velocity changes

an object’s velocity changes if either its speed or direction changes Changing Velocity an object’s velocity changes if either its speed or direction changes If a bus continues to travel at the same speed but turns left, it’s velocity changes. If it swerves to avoid hitting a cat, its velocity changes

A car travels NW 100 meters in 4 seconds A car travels NW 100 meters in 4 seconds. What is the velocity of the car? 25 m/s NW

Acceleration – is the rate at which velocity changes An object accelerates if its speed, direction, or both change Most of the time objects do not travel at a constant speed. So speed is determined by using an average speed.

Positive Acceleration Negative Acceleration Most of the time objects do not travel at a constant speed. So speed is determined by using an average speed.

V = Vf - Vi t Calculating Average Accerleration is expressed in m/s2 i If a bus continues to travel at the same speed but turns left, it’s velocity changes. If it swerves to avoid hitting a cat, its velocity changes i t

A plane passes over point A at a velocity of 240 m/s north A plane passes over point A at a velocity of 240 m/s north. Forty seconds later, it passes over point B at a velocity of 260 m/s north. What is the plane’s average acceleration? .5 m/s2

What is the average acceleration of a subway train that speeds up from 9.6 m/s to 12 m/s in .8 s on a straight section of track? 3 m/s2

A meteoroid changed velocity from 1. 0 km/s to 1. 8 km/s in 0 A meteoroid changed velocity from 1.0 km/s to 1.8 km/s in 0.03 seconds. What is the acceleration of the meteoroid? 26.7 km/s2

The more details you have, the better off you will be in the future (hint hint) Describing position map (answer all of the questions) Write 1 positive statement about your classmates work Write 1 (constructive criticism) statement about what your classmate can improve on. Then turn it in to the basket Front – title + a creative drawing Inside Flap 1 – definition Inside flap 2 – formula Back page – 2 practice problems