Category Archives: Mechanics

Air Pucks

Demo: ME-F-AP
Pira Index: 1F 30.11

Lab Equipment  Directions
  1. air pucks
  2. 4 AA batteries
Install batteries when setting up and remove batteries when putting away.
  1. Turn on and place on a hard surface and watch them glide.

Other experiments:

Motion on an inclined plane: Use a motion sensor to measure the acceleration of the puck as it glides down a wide inclined plane. Compare this acceleration to calculated acceleration, and to the acceleration of other objects, such as a sliding block, rolling car, or rolling ball. Attach some mass to the puck (make sure it still glides smoothly) and repeat the measurement.

Collisions and conservation of momentum and energy: Use two or three air pucks to investigate the behavior of objects in collisions. Use a motion sensor for quantitative measurements. For inelastic collisions, attach some hook-and-loop (velcro) fasteners to the bumpers.

Flying Pig

Demo: ME-D-FP
Pira Index: 1D 50.00

Lab Equipment  Directions
  1. flying pig
  1. Plug batteries in pig an hang from ceiling.

Always check to see if he is working properly.

Normal Force

Demo: ME-J-NF
Pira Index: 1J 30.15

Lab Equipment  Directions
  1. 1000g weight
  2. digital balance
  3. blue incline plane
  1. Tape down the digital balance to the incline plane.
  2. Zero the balance before taping down 1000g weight on top of it.
  3. Raise incline and watch weight change.


Demo: ME-G-AC
Pira Index: 1G 20.70

 Lab Equipment  Directions
  1. accelerometer
  2. wooden cart
  3. long board for ramp
  4. wooden block
  1.  Place the accelerometer on the wooden cart (it may have been stored on the cart) and roll it along the table. Note slope of water surface as it increases its speed and at constant velocity
  2. Roll the cart down a ramp and again observe the water surface as the cart accelerates down the ramp.
  3. Optional: Accelerator Cart with pendulum:

Demonstrates: reference frames, real forces and pseudo forces

Young’s Modulus

Demo: ME-R-YM
Pira Index: 1R 20.15

 Lab Equipment  Directions
  1.  tall lab stand
  2. expansion scale with clamp and pointer
  3. hook clamp
  4. iron wire – 28 gauge
  5. parallel clamp
  6. pulley
  7. two small blocks of wood
  8. two 90 degree clamps
  9. five 1kg slotted masses
  10. large weight hanger
  11. goggles
  1.  Set up as shown with lab stand extending over cart (pulley end should not be extended much).
  2. Attach one end of wire securely to hook clamp, run it over scale pointer and pulley, and attach far end of wire to weight hanger.
  3. Add masses on weight hanger noting amount of stretch in wire.
  4. If you continue adding mass until elastic limit is passed, wire stretches beyond its limit of return.
Caution: The wire may break. Protect your eyes and toes.


Happy-Sad Balls

Demo: ME-R-HS
Pira Index: 1R 40.30

 Lab Equipment  Directions
  1.  happy-sad balls
  1.  Show that the balls appear to be identical in size, weight, and appearance.
  2. Simultaneously drop the balls from the same height.
  3. Observe that one ball bounces and the other one does not. Why?


Hooke’s Law II

Demo: ME-R-HO
Pira Index: 1R 10.00

 Lab Equipment  Directions
  1.  lab stand
  2. two 90 degree clamps
  3. two cross bars
  4. set of five Hooke’s law springs with labels indicating ‘k’ values
  5. paper showing ‘k’ ratios
  6. hooked masses: 2-10g, 3-20g, 1-50g, and 1-100g
  1.  Set up as shown. Slide paper of ‘k’ ratios over lower bar. Slide the movable pointers of each spring so all line up with the top of the paper.
  2. Position masses below the spring as follows: 1 – 10g k spring, 2 – 20g k spring, 4 – 40g k spring, 6 – 60g k spring, 10 – 100g k spring
  3. After pointing out that all pointers are aligned with no masses on the springs, add the masses to each spring.
  4. Re-position the bar with the k ratio paper down to show pointers are still in line.


Hooke’s Law Demo

Demo: ME-R-HL
Pira Index: 1R 10.00

 Lab Equipment  Directions
  1.  five springs
  2. five 500 gram hooked masses
  3. crossbar
  4. lab pole
  5. 90 degree clamp
  6. telescope clamp
  7. wood block
  1.  Set up experiment as shown.
  2. Note the displacement that occurs when equal masses are hung from each spring.
  3. Start oscillating each spring.
  4. Also note the different spring constants.