1. Newton’s third Law, Quiz, Review Tuesday, November 17, 2015

2. Tuesday, 11/17 Unit 4: Forces A 5.0 kg rock is at rest on the ground. For each situation below draw a free body diagram (to scale), calculate the forces acting on the rock, and describe the motion (direction and acceleration). 1. The rock is at rest on the ground. Calculate it’s weight. 2. A rope is tied to the rock and is used to pull the rock upwards. The rock accelerates at 5.0 m/s 2. Calculate the force of tension in the rope. 3. As the rock is pulled upwards, the force exerted by the rope is reduced to 40 N. Calculate the acceleration of the rock. Upcoming dates  Tuesday, 11/17 – Quiz  Tuesday, 11/17 – Review due when the late bell rings  Thursday, 11/19 – Last day to turn in late work  Thursday, 11/19 – unit 4 test  W/O 11/23 – Thanksgiving Break  Friday, 12/11 - Nine week extra credit due by 4:00 PM

3. Tuesday, 11/17 Unit 4: Forces A 5.0 kg rock is at rest on the ground. For each situation below draw a free body diagram (to scale), calculate the forces acting on the rock, and describe the motion (direction and acceleration). 1. The rock is at rest on the ground. Calculates it’s weight. G: m = 5.0 kgE: F g = (m)(a g )S: F g = 49 N a g = 9.8 m/s 2 U: F g S: F g = (5)(9.8) Rock is at rest, forces are balanced, and acceleration is zero. Upcoming dates  Tuesday, 11/17 – Quiz  Tuesday, 11/17 – Review due when the late bell rings  Thursday, 11/19 – Last day to turn in late work  Thursday, 11/19 – unit 4 test  W/O 11/23 – Thanksgiving Break  Friday, 12/11 - Nine week extra credit due by 4:00 PM

4. Tuesday, 11/17 Unit 4: Forces A 5.0 kg rock is at rest on the ground. For each situation below draw a free body diagram (to scale), calculate the forces acting on the rock, and describe the motion (direction and acceleration). 2. A rope is tied to the rock and is used to pull the rock upwards. The rock accelerates at 5.0 m/s 2. Calculate the force of tension in the rope. G: m = 5.0 kgE: F net = (m)(a)S: F net = 25 N a = 5.0 m/s 2 U: F net S: F net = (5)(5) F T = F g + F net F T = 49 +25 F T = 74 N Rock is moving upwards, forces are unbalanced, and acceleration is 5.0 m/s 2 Upcoming dates  Tuesday, 11/17 – Quiz  Tuesday, 11/17 – Review due when the late bell rings  Thursday, 11/19 – Last day to turn in late work  Thursday, 11/19 – unit 4 test  W/O 11/23 – Thanksgiving Break  Friday, 12/11 - Nine week extra credit due by 4:00 PM

5. Tuesday, 11/17 Unit 4: Forces A 5.0 kg rock is at rest on the ground. For each situation below draw a free body diagram (to scale), calculate the forces acting on the rock, and describe the motion (direction and acceleration). 3. As the rock is pulled upwards, the force exerted by the rope is reduced to 40 N. Calculate the acceleration of the rock. G: F T = 40 NE: F net = (m)(a)S: a = 1.8 m/s 2 F g = 49 N F net – 9N (49-40) U: aS: 9 = (5)(a) Unbalanced forces, moving downward, accelerating at 1.8 m/s 2 Upcoming dates  Tuesday, 11/17 – Quiz  Tuesday, 11/17 – Review due when the late bell rings  Thursday, 11/19 – Last day to turn in late work  Thursday, 11/19 – unit 4 test  W/O 11/23 – Thanksgiving Break  Friday, 12/11 - Nine week extra credit due by 4:00 PM

6. Newton’s third Law  Read the text.  In your own words summarize Newton’s Third Law of motion.  Answer the questions at the end of the text.  Check your answers on the key (center lab desk).

7. Cool Down  Two sumo wrestlers are pushing on one another. One has a mass of 300 Kg and the other has a mass of 325 Kg. Sumo wrestler ‘A’ exerts a 50 N force on wrestler ‘B’. What force does wrestler ‘B’ exert on ‘A’?

8. Muddy Point

9. Quiz

10. Kahoot