PHYSICS 7 DEMONSTRATIONS 2005
            Humphrey Maris

9/7 W 1.
a) Galilean incline plane. Plane at a small angle with marks spaced
according to t2 . Observe ball passing marks and correlate with a ticking metronome.
b) Dropping strings of beads. Beads spaced at distances n2 from end land at equal time intervals. Beads equally spaced land at times separated by decreasing increments.

9/9 F 2.
Three meter sticks attached at right angles to make a coordinate system.

9/12 M 3.
a) Simultaneously two balls drop off table. One has a horizontal velocity and one falls straight. Both hit ground at same time.
b) Monkey and gun demonstration.
c) Howitzer and a tunnel. Ball thrown in air and caught.

9/14 W 4.
a) Circular motion with bubble for overhead. A liquid container is attached to the end of a pivot arm. The liquid contains a bubble. Bubble moves towards the center as liquid rotates.
b) Metal strips which model the surface of the earth. Ancient demonstration.
c) Corioli’s force demo with platter and hole in center. Ball is launched towards the center using a ramp. Ball misses center hole if platter is rotating.
First do it without camera. (curves into hole)
Second do it with wireless camera and instant replay.

9/16 F 5.
a) Ring with cut. A transparent ring has a short cut in it and is
Placed on top of the overhead. A ball bearing runs around the inside of the ring. When it comes to the cut does it go straight out radially, continue in a circle or go in a straight line.

9/19 M 6.
a) Coin and feather. Could bring in a chicken. (Large box for chicken)
b) Cavendish experiment from lab.

9/21 W 7.
a) Newton Scales: A spring scale with a weight attached. The scale reads in Newtons. If scale and weight are dropped the scale reads zero.
b) Blackboard Mechanics: Scales, pulleys, masses attached to
blackboard.
c) Block and tackle.
d) Inertia ball. A string hags from a support and is attached to
heavy ball. Another string hangs below the ball. If one pulls slowly on the lower string the upper string breaks. If one pulls fast the lower string breaks.
e) Cork on Rope: A cork is attached to the end of a string which passes through a tube. A weight is attached to the end of the rope. By swinging the cork around the weight can be pulled up.

9/23 F 8.
a) Balance and burning string. Can record onto a videotape and then play back. Includes slow motion instant replay.

9/26 M 9.
a) Bucket with sponge. Pour water into the bucket. Swing bucket
around in a circle in a vertical plane. Explain why the water does not fall out. One can put a sponge in the bucket to hold the water. Then one can pretend to tip the water over a students head at the end of the lecture. Nothing to do with viscosity but this might be a convenient place.

9/28 W 10.
a) Cinder block on a board. Pull block across floor using force scale. Shows static friction is greater than dynamic friction. One can put another block on top of the first block to show the variation of the friction force with normal reaction.
b) Puck on turntable. Aluminum disk on turntable. Put puck on disk. It will slide off if it is too far from the axis of rotation.

9/30 F 11.
a ) Air track with two carts with a spring compressed between them. Held together by a string which is burnt.
b) Air track plus a firecracker between them
c) Water rocket. A bottle is half filled with water. There is a cork in the open end and a tube going to the compressed air supply. When the cork blows out the compressed air in the rocket pushes the water out the back and the rocket flies around the room.

10/3 M 12.
a) Throw dog toy to illustrate center of mass motion.
b) Hang an irregular object from three places to illustrate that the center of mass always lies below the point of support. Could perhaps find a large pretzel to use as the object.
c) Throw an egg and catch it in a sheet. This demonstrates that the change of momentum is the integral of the force over time. One can slow down a particle with a weak force if it acts for long enough. Bring in a chicken for this demo.
d) Newton's Cradle

10/5 W 13.
a) Balls falling down three tracks emerge with the same velocity.
b) Racing balls. Which one will be first?
10/7 F Exam 1
10/10 M Columbus

10/12 W 14.
a) Galileo pendulum. A string pendulum in which the string
contacts a peg when the string moves in one direction. Mass rises to same height on either side of the string.
b) Bowling ball basher. Ball hangs from a pendulum in front of
professor's nose. It is let go and if not pushed will come back exactly to the same spot.

10/14 F 15.
Ball rolling across the top surface of a hemisphere.

10/17 M 16.
a) Newton’s cradle demonstration.
b) Track demos. Two carts bouncing off each other. Collisions of two carts with Velcro between them.
c) Drop a basket ball to the ground with a tennis ball on top of it. Tennis ball bounces up to the ceiling.
d) Pair of balls, one very elastic and one inelastic. Sad and happy balls.
e) Kik-dis pucks.
f) Red Ball express.

10/19 W 18.

10/21 F 19.
a) Hula hoop used as a prop.
b) Bike wheel with handles used as a prop.

10/24 M 20.

10/26 W 21.
a) Atwell’s machine with a massive pulley.
b) Rod with cross beam with weights attached to it so that one can vary the moment of inertia. Rod has a three pulleys of different radii attached to it. Use as an Atwood’s machine.
c) Bike wheel with string attached to the edge. Pull string fast and break it. Demonstrates rotational inertia.
d) Astronaut video.

10/28 F 22.

10/31 M 23.
a) A physical pendulum of some sort. Need to be able to vary the position of the pivot point.
b) Simple pendulum of varying length.
c) Same simple pendulum with a metronome set to the small amplitude vibrational frequency. Increase amplitude to show that the period increases.

11/2 W            24.
a) Wheel with small axle rolling down a ramp. Wheel accelerates very slowly while on ramp but accelerates away when it reaches the floor.
b) Roll objects down a hill (disc, hoop, sphere).
c) Bird with lead weights in wings so that it balances on its nose.
d) Set of 9 planks hanging over the edge of a table

11/4 F  25.
a) Yo-yo on string.
b) Bowling ball sliding and then rolling. (Use large box with foam asa catcher)
c) Bike chain. Spin this and see it slide across the floor.
d) Falling disk demo. One disc rotates and the other just falls.

11/7 M 26.
a) Giant wooden yo-yo. Vary the angle at which one pulls and yo-yo either rolls string onto it or off of it.
b) Broomstick and wine glasses.

11/9 W            27.
a) Bicycle wheel and stool demo.
b) A spinning football to throw.
c) Disk with weights attached. Demonstrate balanced and unbalanced rotation.
d) Bring in my router from home.

11/11 F            Exam 2

11/14 M           29.
a) Simple gyroscope with air bearing.
b) Tops.
c) Bike wheel with an axle which can be supported at one end.
d) Big gyroscope.

11/16 W          30.
a) Foucault pendulum to show the rotation of the earth.
d) Big gyroscope.

11/18 F            31.      

11/21 M           32.         

11/23 W          33.
Video:  Feynman Lecture # 1, The Law of Gravitation.         

11/25 F 
Thanksgv.         

11/28 M           35.
No demo

11/30 W          36.
Examples of oscillators: pendulum, mass plus spring, torsional oscillator. One can vary the position of the weights on the torsional oscillator.

12/2 F  37.
Tuning fork and wax with microphone, amplifier and oscilloscope.

12/5 M 38.
a) Breaking glass with sound.
b) Resonance demonstration with mechanical driver of spring and mass.

12/7 W
a) Driven resonance Water ballon demo, show phase at resonance. Note: There is some question about the demo.  Maybe it should not be used?
b) Chaotic pendulum with second arm attached.

12/9 F
Review