Physics I: Mechanics

Phys 131, Spring 2018

Hugel 020
Physics Department
Lafayette College
730 High St.
Easton, PA 18042

Phone: (610) 330-5207
Email: thomasbd@lafayette.edu

Contact Info

Physics at Lafayette

Other Resources

Powers of Ten: Classic short film by Charles and Ray Eames which shows what the universe looks like on different distance scales.

Strobe of a Falling Ball: A stop-motion image of a falling ball is constructed from a set of still photos taken with the aid of a strobe light.
Golf-Ball Launcher: A golf ball is launched upward from a moving cart and lands back in the cart.
Monkey and Gun: In this classic demonstration of the independence of motion in the horizonatal ad vertical directions, a golf ball is aimed at a plush monkey suspended by an electromagnet from a tall pole. At the moment the ball is launched, the electromagnet is turned off and the monkey begins falling. However, since both ball and monkey accelerate vertically downward at the same rate, the ball nevertheless strikes the monkey in mid-air.

Fire Extinguisher: A demonstration of Newton's third law in which a person seated on a skateboard propels himself forward using a fire extunguisher.

Bowling-Ball Pendulum: Dramatic demonstration of the conservation of mechanical energy using a pendulum which consists of a bowling ball tied to the end of a rope.

Two-Dimensional Collisions: Footage of collisions between pairs of pucks on an air-hockey table. Photos taken under black light that show the trajecories of the pucks before and after each collision are also shown at the end of the video. These videos and photos illustrate the conservation of linear momentum.
Newton's Cradle with Unequal Masses: A modified version of Newton's cradle involving a metal ball and two ping-pong balls which provides an example of the more general case of elastic collisions between objets of unequal masses.
Centers of mass: Highlighting the trajectory of the center of mass of various complicated objects thrown up in the air by painting the center of mass with fluorescent paint and viewing the objects under black light as they move. No matter how complicated the object, the center of mass traces out a perfect parabola.
Push Me, Pull You: Highlighting the motion of the center of mass of two carts on an air track connected by a spring, once agin by painting the center of mass and viewing its motion under black light. The center of mass moves in a straight line with constant velocity down the track until acted upon by an external force (an impulse resulting from a collision beween one of the carts and the bumper on the far end) and then travels back with a constant velocity in the other direction.

Bicycle Wheel Gyroscope: A bicycle wheel suspended by a rope from one of end of its axle is set spinning in the horizontal plane. The wheel is then repositioned into the vertical plane. The axle begins to precessing around the vertical axis.

Simple Harmonic Motion and Circular Motion: A pendulum oscillated back and forth in front of a peg attached to a rotating turntable with the same period as the penulum. The shadow of the peg projected by a spotlight follows the pendulum as it moves.
Spray-Paint Oscillator: A can of spray paint attached to a pair of springs oscillates up and down and traces out a sine wave on a roll of paper.
Resonant Tuning Forks: Demonstrating resonance behavior and beat frequencies using a pair of tuning forks.