DUE 12/15 AP PHYSICS WEEK 16 HOMEWORK RUBRIC PAGE 147-148

STUDENT NAME ______PERIOD ______FINAL SCORE ______

AREA NEWTON’S LAWS POINTS CORNEL NOTE FORMAT: Heading, Page Set Up, Legible, Organized, Color 5 How is Newton’s third law different from the first 2 laws 15 The first and second laws apply to single objects and the forces that act on them. Newton’s third law of motion addresses interactions between objects, or between objects and the environment In your own words explain Newton’s 3rd law of motion (provide an example) 15 For every force or action and equal force or action occurs in the opposite direction Define and relate the terms action forces and reaction force. 15

Action forces are the initial created for while the reaction force although equal and opposite is created by the other object in response to the action force. reaction is the equal and opposite partner of the action force of your wheel against the ground. The reaction force is what moves you Provide an example of How Normal forces demonstrate Newton’s third law of motion 15 . The box pushes down on the table with a force equal to its weight. That force acts on the table. The reaction force is the table acting back up on the box. The forces that hold objects up are reaction forces. List the action reaction labels on page 147 and provide an example for each label. 15

All forces come in pairs. If one is the action, then the other is the reaction.- A PUNCH IS AN ACTION THE FORCE YOU FEEL AGAINST YOUR FIST IS THE REACTION.

Action–reaction forces are always exactly equal in strength and opposite in direction. The action and reaction forces always act on different objects, so they never cancel each other out.- THE HARDER YOU HIT A TABLE THE MORE YOUR HAND HURTS

They also act simultaneously with each other: THE MOMENT I HIT THE TABLE IT FEEL THE FORCE FROM THE TABLE. Complete questions 1 and 2 on page 148 25 Which of Newton’s three laws of motion best applies to each statement? a. A 120 lb student sat on a stool, and the stool applied a 120 lb normal force to the student. Newton’s third law. The force of the student pressing down on the stool and the normal force from the stool pressing up on the student are an action–reaction pair of forces. b. The spacecraft cruised toward the North Star at a constant 500 m/s through the vacuum of interstellar space. Newton’s first law. In the absence of a net force, the spacecraft remains in a constant state of motion. c. Now that the moving van was full, its driver had to apply more force to reach highway speed before the on-ramp ended. Show Newton’s second law. With more mass, the van needs more force to achieve the same acceleration 2. Two students are debating the meaning of Newton’s laws of motion. Arjun: “See that guy pushing the crate across the gym floor? He’s working hard, but the crate never speeds up. No acceleration! Newton’s second law can’t be right!” Buell: “I wonder. Newton’s second law has to do with net force, which is the total force you are left with after you add up all the forces pushing on something. I think there is another force at work.” Which student is correct, and why? Buell is correct. Newton’s second law states that an object’s acceleration is proportional to the net force acting on an object. In the direction of the crate’s motion, the worker is pushing just hard enough to overcome friction between the crate and the floor—but no harder. (He did have to push harder in order to start the crate moving.) In the vertical direction, the crate’s weight equals the normal force applied by the floor. Sure enough, the crate is not accelerating along the vertical axis either! (It remains at the level of the floor.) TOTAL 105 GRADED BY ______DUE 12/15 AP PHYSICS WEEK 16 HOMEWORK RUBRIC PAGE 147-148

STUDENT NAME ______PERIOD ______FINAL SCORE ______

AREA NEWTON’S LAWS POSSIBLE ACTUAL POINTS POINTS CORNEL NOTE FORMAT: Heading, Page Set Up, Legible, Organized, Color 5 How is Newton’s third law different from the first 2 laws 15 In your own words explain Newton’s 3rd law of motion (provide an example) 15 Define and relate the terms action forces and reaction force. 15 Provide an example of How Normal forces demonstrate Newton’s third law of motion. 15 List the action reaction labels on page 147 and provide an example for each label. 15 Complete questions 1 and 2 on page 148 25 1 a. Newton’s third law. The force of the student pressing down on the stool and the normal force from the stool pressing up on the student are an action–reaction pair of forces. b. Newton’s first law. In the absence of a net force, the spacecraft remains in a constant state of motion. c. Newton’s second law. With more mass, the van needs more force to achieve the same acceleration 2. Buell is correct. Newton’s second law states that an object’s acceleration is proportional to the net force acting on an object. In the direction of the crate’s motion, the worker is pushing just hard enough to overcome friction between the crate and the floor—but no harder. (He did have to push harder in order to start the crate moving.) In the vertical direction, the crate’s weight equals the normal force applied by the floor. Sure enough, the crate is not accelerating along the vertical axis either! (It remains at the level of the floor.) TOTAL 105 GRADED BY ______

DUE 12/15 AP PHYSICS WEEK 16 HOMEWORK RUBRIC PAGE 147-148

STUDENT NAME ______PERIOD ______FINAL SCORE ______

AREA NEWTON’S LAWS POSSIBL ACTUAL E POINTS POINTS CORNEL NOTE FORMAT: Heading, Page Set Up, Legible, Organized, Color 5 How is Newton’s third law different from the first 2 laws 15 In your own words explain Newton’s 3rd law of motion (provide an example) 15 Define and relate the terms action forces and reaction force. 15 Provide an example of How Normal forces demonstrate Newton’s third law of motion. 15 List the action reaction labels on page 147 and provide an example for each label. 15 Complete questions 1 and 2 on page 148 25 1 a. Newton’s third law. The force of the student pressing down on the stool and the normal force from the stool pressing up on the student are an action–reaction pair of forces. b. Newton’s first law. In the absence of a net force, the spacecraft remains in a constant state of motion. c. Newton’s second law. With more mass, the van needs more force to achieve the same acceleration 2. Buell is correct. Newton’s second law states that an object’s acceleration is proportional to the net force acting on an object. In the direction of the crate’s motion, the worker is pushing just hard enough to overcome friction between the crate and the floor—but no harder. (He did have to push harder in order to start the crate moving.) In the vertical direction, the crate’s weight equals the normal force applied by the floor. Sure enough, the crate is not accelerating along the vertical axis either! (It remains at the level of the floor.) TOTAL 105 GRADED BY ______