AP Physics 1 Lab Manual Overview

• Foundational understanding of displacement, position, velocity, and acceleration
• Ability to define average velocity, average acceleration, instantaneous velocity, and instantaneous acceleration

3.A.1.1: Express the motion of an object using narrative, mathematical, and graphical representations.

3.A.1.2: Design an experimental investigation of the motion of an object.

3.A.1.3: Analyze experimental data describing the motion of an object and be able to express the results of the analysis using narrative, mathematical, and graphical representations.

• Newton’s first law
• Net force is the vector sum of the forces acting on an object or system.
• A system is a collection of two or more objects that directly or indirectly affect each other by force and/or change in momentum.

3.B.1.1: Predict the motion of an object subject to forces exerted by several objects using an application of Newton’s second law in a variety of physical situations, with acceleration in one dimension.

3.B.1.2: Design a plan to collect and analyze data for motion (static, constant, or accelerating) from force measurement, and carry out an analysis to determine the relationship between the net force and the vector sum of the individual forces.

3.B.1.3: Re-express a free-body diagram into a mathematical representation, and solve the mathematical representation for the acceleration of the object.

3.B.2.1: Create and use free-body diagrams to analyze physical situations to solve problems with motion qualitatively and quantitatively.

• Determining the acceleration of an object from the slope of its velocity versus time graph
• Calculating the gravitational force of an object
• Using the net force on an object and the object’s mass to:
  1) develop a free-body diagram and
  2) derive a mathematical expression for the object’s acceleration in one dimension

3.B.1.1: Predict the motion of an object subject to forces exerted by several objects using an application of Newton’s second law in a variety of physical situations, with acceleration in one dimension.

3.B.1.2: Design a plan to collect and analyze data for motion (static, constant, or accelerating) from force measurement, and carry out an analysis to determine the relationship between the net force and the vector sum of the individual forces.

• Friction is a contact force between two surfaces. It opposes the motion of the surfaces.
• There are two types of frictional force: static and kinetic. Static frictional force is usually greater than kinetic frictional force.
• Newton’s Second Law: The acceleration of an object is proportional to the net force acting on that object.
• Students should be able to analyze the motion of an object and draw free-body diagrams describing the forces acting on that object.

3.C.4.1: Make claims about various contact forces between objects based on the microscopic cause of these forces.

3.C.4.2: Explain contact forces (tension, friction, normal, buoyant, spring) as arising from interatomic electric forces and that they therefore have certain directions.

• The one-dimensional motion of an object moving with constant acceleration can be described using the kinematic equations.
• The two-dimensional velocity of a projectile is described using component vectors in the vertical and horizontal directions. Each component vector can be analyzed independent from the other, so long as both are constrained to the same timeframe.
• Students should be able to draw free-body diagrams that include force and component vectors for objects in motion.

3.E.1.3: Use force and velocity vectors to determine qualitatively or quantitatively the net force exerted on an object and qualitatively whether the kinetic energy of that object would increase, decrease, or remain unchanged.

3.E.1.4: Apply mathematical routines to determine the change in kinetic energy of an object given the forces on the object and the displacement of the object.

• Conservative forces are those which store energy in a useful form when objects within a system interact. Examples of conservative forces include gravity, gravitational potential energy, and friction.
• Newton’s Second Law of Motion for linear motion states that a net force causes an object to accelerate.
• Objects near earth’s surface accelerate due to the gravitational field, with a magnitude of 9.8 m/s².

5.B.4.1: Describe and make predictions about the internal energy of systems.

5.B.4.2: Calculate changes in kinetic energy and potential energy of a system using information from representations of that system.

• Kinetic energy is a component of an object’s total mechanical energy and is equal to 1/2$\large mv^2$, where $\large m$ is the object’s mass and $\large v$ is the object’s speed.
• Conservative forces are forces that do work on an object regardless of the path the object is moved through. The net work done on an object whose total displacement is zero, is also zero. Gravity is a conservative force.
• Positive work is only done on an object by the component of a nonzero net force acting in the direction of the object's displacement.

4.C.2.1: Make predictions about the changes in the mechanical energy of a system when a component of an external force acts parallel or antiparallel to the direction of the displacement of the center of mass.

4.C.2.2: Apply the concepts of conservation of energy and the work-energy theorem to determine qualitatively and/or quantitatively that work done on a two-object system in linear motion will change the kinetic energy of the center of mass of the system, the potential energy of the systems, and/or the internal energy of the system.

• The momentum of an object is equal to the product of its mass and velocity. For a system that is not influenced by outside forces, the total momentum of the system is conserved. This extends to objects experiencing two types of collisions: elastic and inelastic.
• An elastic collision is a type of collision in which the objects involved in the collision bounce off each other without the loss of kinetic energy from the total object system.
• An inelastic collision is a collision type in which the system consisting of the objects involved in the collision experiences a loss of kinetic energy due to other changes in the system, such as the objects sticking to each other or the deformation of the objects in the collision. These interactions convert some kinetic energy to thermal energy.
• Kinetic energy is a component of an object's total mechanical energy.

5.D.1.3: Apply mathematical routines appropriately to problems involving elastic collisions in one dimension and justify the selection of those mathematical routines based on conservation of momentum and restoration of kinetic energy.

5.D.2.2: Plan data-collection strategies to test the law of conservation of momentum in a two-object collision that is elastic or inelastic and analyze the resulting data graphically.

5.D.2.4: Analyze data that verify conservation of momentum in collisions with and without an external frictional force.

• Momentum is a vector quantity defined as the product of an object's mass and its velocity. The momentum of an object can only be changed when a nonzero net force is imparted to the object.
• Impulse is a vector quantity. For constant forces acting on an object, impulse is equal to the product of the force acting on the object and the time interval during which the force is acting.
• For variable forces acting on an object, impulse is equal to the area under the force versus time curve representing the interaction, which can be simplified to the product of the average of the variable force and the time interval during which the force is acting.

3.D.2.3: Analyze data to characterize the change in momentum of an object from the average force exerted on the object and the interval of time during which the force is exerted.

3.D.2.4: Design a plan for collecting data to investigate the relationship between changes in momentum and the average force exerted on an object over time.

• Torque is equal to the product of the perpendicular distance from the axis of rotation to an applied force and the magnitude of the applied force.
• The rotational inertia of point masses increases with increasing distance from the axis of rotation.
• The total rotational inertia of a combination of rigid bodies, mechanically connected, is equal to the sum of their individual rotational inertias assuming the axis of rotation is the same for all.

3.F.2.1: Make predictions about the change in the angular velocity about an axis for an object when forces exerted on the object cause a torque about that axis.

3.F.2.2: Plan data-collection and analysis strategies designed to test the relationship between a torque exerted on an object and the change in angular velocity of that object about an axis.

3.A.1.3: Analyze experimental data describing the motion of an object and be able to express the results of the analysis using narrative, mathematical, and graphical representations.

Students should be familiar with these concepts:

• Drawing free-body force diagrams
• Newton’s Second Law for translational motion
• A rigid body or system is an extended object whose shape and size remain constant when it moves.
• Torque is the rotational equivalent of force.
• Torque is a vector quantity with direction parallel to the axis of rotation.
• For calculations involving torque, the entire weight of an object can be considered to act at a single point, the center of gravity or center of mass of the object.
• A torque is positive when it is applied in the counterclockwise direction and negative when it is applied in the clockwise direction.

3.F.1.1: Use representations of the relationship between force and torque.

3.F.1.2: Compare the torques on an object caused by various forces.

3.F.1.3: Estimate the torque on an object caused by various forces in comparison with other situations.

3.F.1.4: Design an experiment and analyze data testing a question about torques in a balanced rigid system.

3.F.1.5: Calculate torques on a two-dimensional system in static equilibrium by examining a representation or model (such as a diagram or physical construction).

Students should be familiar with these concepts:

• Hooke’s Law
• Newton’s Second Law
• The graphical connection between position, velocity, and acceleration versus time graphs.
• How to sketch a velocity versus time graph based on the shape of a corresponding position versus time graph.

3.B.3.1: Predict which properties determine the motion of a simple harmonic oscillator and what the dependence of the motion is on those properties.

3.B.3.2: Design a plan and collect data in order to ascertain the characteristics of the motion of a system undergoing oscillatory motion caused by a restoring force.

3.B.3.3: Analyze data to identify qualitative and quantitative relationships between given values and variables (i.e., force, displacement, acceleration, velocity, period of motion, frequency, spring constant, string length, mass) associated with objects in oscillatory motion and use those data to determine the value of an unknown.

3.B.3.4: Construct a qualitative and/or quantitative explanation of oscillatory behavior given evidence of a restoring force.

Students should be familiar with these concepts:

• The basic concept of periodic motion as a result of a restoring force.
• Period is a quantity that describes the time it takes a pendulum to complete one full cycle of motion
• The graphical connection between position, velocity, and acceleration versus time graphs.
• How to sketch a velocity versus time graph based on the shape of a corresponding position versus time graph.

3.B.3.1: Predict which properties determine the motion of a simple harmonic oscillator and what the dependence of the motion is on those properties.

3.B.3.2: Design a plan and collect data in order to ascertain the characteristics of the motion of a system undergoing oscillatory motion caused by a restoring force.

3.B.3.3: Analyze data to identify qualitative and quantitative relationships between given values and variables (i.e., force, displacement, acceleration, velocity, period of motion, frequency, spring constant, string length, mass) associated with objects in oscillatory motion and use those data to determine the value of an unknown.