1. Classical Mechanics Midterm 1 and Newton’s Laws
Unit 4 Main Points/Checkpoints
Unit 4 Relevant Equations and How to use them…
Unit 4 Homework Hints…
Midterm 1 Exam Discussion

2. Main Points

3. Main Points

4. Newton’s 2nd Law Acceleration is caused by force.
A bigger mass makes this harder 4

5. Checkpoint 1
The net force on a box is in the positive x direction. Which of the following statements best describes the motion of the box :
A) Its velocity is parallel to the x axis
B) Its acceleration is parallel to the x axis
C) Both its velocity and its acceleration are parallel to the x axis
D) Neither its velocity or its acceleration need be parallel to the x axis

6. CheckPoint
The net force on a box is in the positive x direction. Which of the following statements best describes the motion of the box :
A) Its velocity is parallel to the x axis
B) Its acceleration parallel to the x axis
C) Both its velocity and its acceleration are parallel to the x axis
D) Neither its velocity or its acceleration need be parallel to the x axis
B) Net force causes acceleration, but it does not necessarily say anything about the direction of the velocity. 6

7. Vertical
Horizontal
jet

8. jet

9. jet

10. The motion of an object is affected by only the forces acting upon it.
Newton’s 3rd Law
The motion of an object is affected by only the forces acting upon it.

11. a 5M F M Force on Two Masses
A force F is applied to a small block, that pushes a larger block. The two blocks accelerate to the right. Compare the NET FORCE on the block with mass M, to the net force on the block with mass 5M.
A) FM < F5M
B) FM = F5M
C) FM > F5M a 5M F M

12. Same acceleration, so larger mass has larger net force.
Force on Two Masses
A force F is applied to a small block, that pushes a larger block. The two blocks accelerate to the right. Compare the NET FORCE on the block with mass M, to the net force on the block with mass 5M.
A) FM < F5M
B) FM = F5M
C) FM > F5M
Net Force
Same acceleration, so larger mass has larger net force. a 5M F M 12