Balance of gravity and upward force; statement of Newton's third law.

Action and reaction between two blocks, in a garden hose, and in a balloon.

Newton's third law demonstrated through spinning engine propelled by steam.

Third law used to calculate acceleration of earth towards and away from tossed apple.

Weight defined; weight on accelerating scales calculated; free-fall defined.

Acceleration and tension calculated for two masses suspended over a pulley.

Results interpreted as masses become unbalanced; gain and loss of weight in free-fall.

Calculation of tension at top and bottom of loop for mass swinging in vertical plane.

Demonstration that a gallon of water is weightless in free fall during jump from table.

Demonstration that barbell is weightless in free-fall, then very heavy on impact.

Definition, including normal force; μ_s = ∠tan α proven; method for determining μ_s.

Demonstration of dependence of μ_s on surface, but not surface area or mass.

System of block sitting on inclined plane, connected to hanging block; calculation of conditions when block is falling or is static.

Numerical calculations for pulley/plane system, including interpretation and calculation of acceleration and tension.

Demonstration of pulley/plane system; additional mass hangs, then falls; explanation of changing friction.

Explanation of friction elimination by hydroplaning and air tracks, with brief demonstrations.

Video of device that travels on cushion of CO₂ on plate glass; friction so low a flea can pull a large book on the device.

Calculation of acceleration for two blocks suspended over pulley with friction from masses and moment of inertia.

Step-by-step strategy for solving motion problems. Ideal pulleys, pegs, and strings are introduced. Includes a number of motion examples.

Conditions of equilibrium for particles and rigid bodies; torque axis; center of gravity; center of mass demonstration; stable and unstable equilibrium; coupled forces; equilibrium problem-solving strategy with several examples.

Definition, including an example of identifying action/reaction pairs.

Step-by-step strategy for solving motion problems. Ideal pulleys, pegs, and strings introduced. Includes a number of motion examples.

Conditions of equilibrium for particles and rigid bodies; torque axis; center of gravity; center of mass demonstration; stable and unstable equilibrium; coupled forces; equilibrium problem-solving strategy with several examples.

Statement, including an example of identifying action/reaction pairs.

Newton's first law defined; Newton's second law defined (F=ma); Newton's third law defined; inertial reference frames defined.

Direction and magnitude of friction; static and kinetic friction; coefficient of friction.

Direction and magnitude of spring force; spring constant; springs in parallel and series.

Newton's three laws of motion defined with a sentence each.

Action-reaction force pairs; tension in a rope; free body force diagram.

Using special cases and dimensional analysis to determine which acceleration for system is correct.

Solution (PDF)^#

3-part problem; calculating tension in wire, critical angle, and safe speed for flight.

Solution (PDF)

Forces acting on systems of two or more bodies. Solution not included.

Forces acting on two blocks connected and suspended by strings. Solution not included.

Forces acting on a passenger in a turning car. Solution not included.

Forces acting on systems of multiple bodies. Solution not included.

Forces acting on moving and stationary blocks sitting on a surface. Solution not included.

Forces acting on moving and stationary blocks sitting on a surface. Solution not included.

Forces acting on horizontal and vertical springs. Solution not included.

Friction and acceleration; which forces must be known to solve for energy and momentum; kinetic energy and momentum in a collision. Solution not included.

Forces and accelerations acting on two blocks connected by strings.

Solution (PDF)^#

Forces, including friction, acting on a cart connected to a block suspended from a pulley.

Solution (PDF)^#

Static friction between a glass and a tablecloth.

Solution (PDF)^#

Comparing the gravitational force on a car and the normal force of the ground on the car. Solution not included.

Forces acting on a scale with a person jumping from it. Solution not included.

Normal force exerted on a person in an accelerating elevator. Solution not included.

Force needed to push a crate across a floor as a function of the surface area in contact with the floor. Solution not included.

Motion of an object sliding on an inclined surface, with friction. Solution not included.

Tension in a rope pulling a block with friction. Solution not included.

Tension in a string connecting a moving cart and a hanging weight via a pulley. Solution not included.

Forces acting on a person standing in an accelerating elevator. Solution not included.

Force applied by horse teams to an evacuated hollow metal sphere. Solution not included.

Force acting on the string of a descending yo-yo. Solution not included.

Force acting on the string of an ascending yo-yo. Solution not included.

Acceleration of a system of multiple masses and pulleys. Solution not included.

Relationship between spring constants of springs used to suspend a mass. Solution not included.

Forces acting on a cube lying on a spinning turntable. Solution not included.

Drawing free body diagrams for tug-of-war.

Solution (PDF)^#

Motion of an object sliding off an inclined roof and falling to the ground.

Solution (PDF)^#

Approximating the force law acting between magnets.

Solution (PDF)

Motion of two unequal masses suspended by a string over a rod.

Solution (PDF)

Kinetic vs. static friction and sign; magnitude of horizontal force on suitcase.

Solution (PDF)

3-part problem; drawing free-body diagram and finding acceleration; force required to slide top block relative to bottom.

Solution (PDF)^#

Forces acting in systems of two or more bodies.

Solution (PDF)

Dynamics of an astronaut pushing a block on a surface in outer space.

Solution (PDF)

Motion of and forces acting on a jumping basketball player.

Solution (PDF)

Dynamics of a bead of water on the windshield of an accelerating car.

Solution (PDF)

Dynamics of a suitcase placed on a moving conveyor belt.

Solution (PDF)

Dynamics of a system of a mass suspended from a vertical spinning rod by a string and pulley.

Solution (PDF)

4-part problem; finding acceleration, tension, time, and speed for mass on table to reach pulley while other mass hangs.

Solution (PDF)

4-part problem; drawing free-body diagram and finding v, T for object; maximum speed with friction.

Solution (PDF)

Determining upward speed from a jump given force exerted on the floor.

Solution (PDF)

Effect of lifting a barbell on scale reading.

Solution (PDF)^#

Motion of a monkey climbing a rope that passes over a pulley and connects to a hanging block.

Solution (PDF)^#

Forces acting on a basketball player jumping to take a shot.

Solution (PDF)^#

Motion of an object sliding off an inclined roof and falling to the ground.

Solution (PDF)^#

Motion of a block on an inclined plane and connected to a second block via a wire that passes over a pulley.

Solution (PDF)^#

Motion of two touching blocks on a frictionless table.

Solution (PDF)^#

Motion of a mass that slides down an inclined plane and compresses a spring.

Solution (PDF)^#

Motion of two blocks on an inclined plane and connected to a third block via a wire that passes over a pulley.

Solution (PDF)^#

Modeling the forces and acceleration acting on a person riding an elevator.

Solution (PDF)^#

4-part friction and rotational kinematics problem; drawing a free-body diagram, calculating tensions, and finding unknown mass.

Solution (PDF)