Take out your morning article and begin working silently.

When you finish, you may take a book from the bookshelf.

Agenda: Homework and flash cards due Friday.

1. Explain the motion of [figure a] in the picture. Be sure to describe the reference directions.

2. What is the reference point in this example?

7.P.1.2 Explain the effects of balanced and unbalanced forces acting on an object (including friction, gravity and magnets)

Vocabulary Words

1. unbalanced force

2. balanced force

3. mass

4. friction

5. gravity

6. inertia

7. velocity

8. newtons

9. magnets

10. force

11. frame of reference

Balanced Force

Balance forces are two forces acting in opposite directions on an object, and equal in size. Anytime there is a balanced force on an object, the object stays still or continues moving continues at the same speed and in the same direction.

Unbalanced Force

1. When two forces acting on an object are not equal in size.

2. Unbalanced forces cause: a still object to move, an object to speed up or slow down, a moving object to stop, a moving object to change direction.

Magnet

An object that is surrounded by a magnetic field and that has the property, either natural or induced, of attracting iron or steel.

newton

(symbol: N) is the International System of Units (SI) derived unit of force.

Notebook Title: Speed and Motion

Testable Question: How can you measure speed?

= Raise your hand to ask questions during the lab

= stay positive and work as a team!

Motion

Definition: A change in position over time.

The ball moved from position 6 to position 3.

1 2 3 4 5 6 7 8 9

Speed

Definition: The rate of motion. (how fast motion happens)

Speed is the measure of how fast something moves or the distance it moves, in a given time.

Ball 1 moved 5 meters in 2 seconds.

(Slower speed)

Ball 2 moved 10 meters in 2 seconds.

(Faster speed)

Calculating Speed

speed = distance ÷ time

Units: meters/seconds (m/s) miles/hour (mph)

kilometers/hour (km/h)

1. If something travels 50 miles in one hour, what is its speed?

2. If something travels 4 meters in one second, what is its speed?

3. If something travels 10 miles in two hours, what is its speed?

= 50 miles per hour

= 4 meters per second = 4 m/s

= 5 miles per hour

50 miles

1 hour

4 meters

1 second

10 miles

2 hours

CORNELL SYTLEQuestion NotesWhat is speed? Speed is the measure

of how fast something moves or the distance it moves in a given amount of time. (RATE of MOTION)

How are speed and position related? (hint: the library is 2 blocks away or the library is 5 minutes away)

Speed and position both deal with where an object is.

Question NotesWhat is the formula used to calculate speed?

Speed = distance divided by time

S=d/t

Practice Calculating Speed1. A man runs 200 m in 25 s. What is his speed?

2. If you travel 100 m in 50 s, What is your speed?

3. A women traveled 500 m in 20 s. What was her speed?

4. A wheelchair racer completes a 100 meter course in 20 seconds.

200 m / 25 s = 8 meters per second

100 m / 50 s = 2 meters per second

500 m / 20 s = 25 meters per second

100 m / 20 s = 5 meters per second

Speed Triangles!

Flip over your note sheet to see how they work!

D

S T÷

x

1. Speed = _______ _______

S

D

T

÷

x

Distance

Time

2. Distance = _______ _______

S

D

T

÷

x

Speed

Time

3. Time = _______ _______

S

D

T

÷

x

Distance

Speed

4. Distance = 10 meters, Time = 1 sec.Speed =

S

10 m

1 s

÷

x

5. Distance = 50 meters, Time = 10 sec.Speed =

S

D

T

÷

x

50 meters

10 seconds

5 m/s

6. Distance = 80 miles, Time = 2 hoursSpeed =

S

D

T

÷

x

80 miles

2 hours

40 m/h

7. Distance = 80 miles, Speed = 40 miles/hourTime =

40 miles/hour

80 miles

T÷

x

Sometimes, speed questions are word problems. Just set up your speed triangle!

1. Joe jogged for 1 hour. He ran 6 miles. What was his speed in miles/hour?

2. Alex jogged for 2 hours. He ran 4 miles. What was his speed in miles/hour?

6 miles / 1 hour = 6 m/h

4 miles / 2 hours= 2 m/h

3. Jose threw a ball. It traveled 50 meters in 5 seconds. What was its speed in meters/second?

4. Ms. Reynolds was going 60 miles/hour on the freeway. How far did she get after 1 hour?

5. Ms. Wright was going 60 miles/hour on the freeway. How far did she get after 2 hours?

50 meters/ 5 seconds= 10 m/s

60 miles x 1 hour = 60 miles

60 miles x 2 hours = 120 miles

Can you calculate speed with speed? Use speed triangles to solve practice problems.

The first person in each table to get all correct will win a prize! Work independently (silently).Raise your hand if you have a question.Be on task!

Exit Ticket

1. Speed = ________ _________

2. A train travels for 3 hours. It goes 90 miles. What was its speed?

3. A car is going 60 miles/hour. How far will it go in half an hour?

4. A boat is going 25 miles/hour. How long will it take for it to travel 100 miles?

5. 1 mile/minute = ___ miles/hour