Download Unit 4: Newton`s Laws Lab Activities: Objectives

Unit 4: Newton’s Laws
Reading and Homework: Tipler Chapter 4 in full.
Problem Set
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2
3
4
5
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9
Reading
Chap/Sec
4/1-2
4/3
4/4
4/4
4/5
4/5
4/5
4 / 6-7
Problems
1, 6, 26, 27, 28, 29, 31, 32, 37
(2nd Law)
7, 9, 38, 39, 40
(Mass & Weight)
11, 13, 20, 21, 34 & Gravity Interview
(3rd Law)
19, 23, 36, 41, 42
(Contact Forces)
44, 46, 47, 48, 49
(Free-Body Diagrams)
54, 55, 56, 57, 61
(FB Diagrams & Inclined Planes)
63, 65, 66, 67
(Elevator Problems)
rd
14, 16, 68, 69, 78
(3 Law & Problems with > 1 object)
3, 5, 12, 18, 22, 24, 58, 91, 96,
(Review)
Lab Activities:
• Inertia Activities
• Empirical Forces
• Tension Problems
• Investigating Forces Activity
• Springs and Hooke’s Law Lab
• Recognizing and Interpreting Freebody Diagrams
Objectives
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Define force and describe the 4 basic forces, their relative strengths, and some familiar
examples.
State the first law of motion and demonstrate an understanding of the concept of inertia.
State the 2nd law of motion in mathematical terms, defining each one.
Define the standard unit of force, the Newton (N).
Use the second law in problem solving.
Demonstrate an understanding of the meaning of net force and be able to calculate the
acceleration that results.
Distinguish between the effects of inertia and friction.
Distinguish between mass and weight.
Use the relationship W = mg to calculate an object’s weight when given its mass or to
calculate mass when weight is given.
Understand the use of the term apparent weight and “weightlessness” in describing objects
that are partly supported or in freefall.
Explain what causes and what does not cause gravity.
State the third law of motion and understand that forces between two bodies act in pairs.
Understand the difference between net force (sum of combined forces acting on one
object) and an action-reaction pair of forces that act on two objects.
Apply Hooke’s Law of restoring forces to springs in compression or tension.
Identify normal forces between solids in contact and relate these forces to a model of
solids consisting of atoms connect to each other by springs.
ARHS AP Physics
F11
Unit 4 Objectives
16. Identify the frictional contact force between objects as a force perpendicular to their
normal force, directed to oppose motion.
17. Explain and use the concept of tension in relationship to the forces acting on an object like
a rope.
18. Apply the equilibrium principle to situations in which normal contact forces, friction forces,
tension forces, and gravity act on a body.
19. Draw and interpret correct free body diagrams for objects acted on by normal forces,
tension forces, friction forces, and gravitational forces.
20. Use free-body diagrams to solve 2nd law problems in cases of:
a. static equilibrium
b. dynamic equilibrium
c. accelerating situations
21. Be able to specify axes, resolve vectors, and identify forces in inclined plane problems.
22. Apply the 3rd law of motion to analyze situations involving 2 objects accelerating together.
From the AP Board:
Newton’s laws of motion
1. Static equilibrium (first law)
Students should be able to analyze situations in which a particle remains at rest, or moves
with constant velocity, under the influence of several forces.
2. Dynamics of a single particle (second law)
a. Students should understand the relation between the force that acts on an object and the resulting
change in the object’s velocity, so they can:
1. Calculate, for an object moving in one dimension, the velocity change that results when a
constant force F acts over a specified time interval.
2. Calculate, for an object moving in one dimension, the velocity change that results when a
force F(t) acts over a specified time interval.
3. Determine, for an object moving in a plane whose velocity vector undergoes a specified
change over a specified time interval, the average force that acted on the object.
b. Students should understand how Newton’s Second Law, , applies to an object subject to forces such
as gravity, the pull of strings, or contact forces, so they can:
1. Draw a well-labeled, free-body diagram showing all real forces that act on the object.
2. Write down the vector equation that results from applying Newton’s Second Law to the
object, and take components of this equation along appropriate axes.
3. Students should be able to analyze situations in which an object moves with specified
acceleration under the influence of one or more forces so they can determine the
magnitude and direction of the net force, or of one of the forces that makes up the net
force, such as motion up or down with constant acceleration.
3. Systems of two or more objects (third law)
a. Students should understand Newton’s Third Law so that, for a given system, they can identify the
force pairs and the objects on which they act, and state the magnitude and direction of each force.
b. Students should be able to apply Newton’s Third Law in analyzing the force of contact between
two objects that accelerate together along a horizontal or vertical line, or between two surfaces
that slide across one another.
c. Students should know that the tension is constant in a light string that passes over a massless pulley
and should be able to use this fact in analyzing the motion of a system of two objects joined by a
string.
d. Students should be able to solve problems in which application of Newton’s laws leads to two or
three simultaneous linear equations involving unknown forces or accelerations.
ARHS AP Physics
2
F11