1. Science Starter What is Newton’s 2nd Law (math equation)
What does net force mean?
If a box is moving at constant speed, what is acceleration?
A box is 5kg If I have a 10N force down and a 15N force left, what is a 3rd force that can cause the acceleration to be up and 1 velo/second?

2. Today’s Agenda Science Starter Unit 2: Newton’s 2nd Law Pretest
Pretest Discussion
Unit 3: 1-Dimensional Motion in Physics
Notes, Discussion, and Introduction

3. Unit 2: Newton’s 2nd Law Pretest
Write all answers on a separate sheet of paper
You may keep any thing you write to study for the Unit 2 test
There are 5 free response questions
You will be given 15 minutes and are graded on effort!
Done? Place everything face down and pick up a sheet from the front…

4. Newton’s 2nd Law Lab Nearly Everyone’s graphs looked similar to this.
What does this tell us about the relationship between force and acceleration?

5. To find acceleration you graphed distance/tock
Slope of this graph was equal to acceleration!
Distance
What other values in life are measured in some distance/time?
Tock

6. One-Dimensional Motion in Physics
Acceleration- how much your velocity changes in one second (slope of change in velocity)
Velocity- how much your position changes in one second (slope of change in position)

8. Example 1
A 4kf box is pushed with a net force of 20N to the right. How fast is it moving if it has been pushed for 4 seconds?

9. Example 2
A 4kg box is pushed for 3 seconds with a net force of 8N to the right. Then, somebody else decides to push back with a force of 12N making the new net force 4N to the left
How fast is the box moving after 5 seconds and in what direction?
At what time other than 0s is the box at rest?

10. Example 3 A ball is thrown up in the air with a velocity of 30 m/s
How man seconds will it take the ball to reach its peak (velocity is 0 m/s at this point)

11. Example 4
A 4kg object is pushed with an unknown force. You observe the object moving at t=2seconds with a velocity of 46 m/s and at t=4 seconds with a velocity of 92 m/s
What is the force on the box?