Category Archives: Measurement

Vertical Force Table

Demo: ME-A-VF
Pira Index: 1A 40.00

 Lab Equipment  Directions
  1.  vertical force table
  2. 4 5g weight hangers
  3. 2 sets of slotted weight
  4. box of small slotted weights
  1.  Set the pulleys at preselected angles and hang a weight hanger from each. Add various weights to the weight hangers to show vector addition and resultant values.

 

Vector Addition

Demo: ME-A-VE
Pira Index: 1A 40.00

 Lab Equipment  Directions
  1.  Foam board triangle
  2. 3 strings attached to plastic triangle
  3. plastic solo cup (marked 11.5g)
  4. clear sipper bottle of water
  5. 2 pulleys on rods
  6. 2 sets of hooked masses
  7. 250 ml graduated cylinder
  8. 2 lab stands
  9. 2 90 degree clamps
  10. 2 C-clamps
  1.  On green string hang 300g, on orange 400g, and on middle (pink) 500g. Using the 3, 4, 5 marked triangle, show that the 2 outer masses form a right angle and that the 500g lines up on hypotenuse.
  2. Green – 200g, -300g. Have students calculate mass to hang on pink string to balance masses 90 degree apart. Hang 360g on the pink to check their calculation. Use 2, 3, 3.6 marked triangle to verify the 90 degree angle.
  3. Green – 100g, orange -150g. Have students calculate mass to hang on pink. Pour a volume of water equal to calculated mass (less cup mass as marked) into a graduated cylinder. Transfer water into hanging cup to check balance.

 

Volume Comparison

Demo: ME-A-VC
Pira Index: 1A 20.00

 Lab Equipment  Directions
  1.  Plastic drink bottle (small)
  2. Bud vase (tall)
  1.  Fill drink bottle with water.
  2. Ask students to predict whether the bud vase will hold more water, same amount of water, or less water than the drink bottle.
  3. Pour water from drink bottle into bud vase.

 

Suitcase Pull

Demo: ME-A-SP
Pira Index: 1A 40.00

 Lab Equipment  Directions
  1.   Heavy briefcase with rope
  2. 40 Newton scale
  1.  Set the briefcase on a piece of carpet such as that on the cart. Attach the scale to the rope and pull, keeping the rope in a horizontal plane. Observe the scale reading.
  2. Now pull with the rope at various angles to the horizontal plane and observe the scale reading.

 

Specific Gravity Cubes

Demo: ME-A-SG
Pira Index: 1A 10.55

 Lab Equipment  Directions
  1.  Set of equal volume cubes
  2. digital scale
  3. stand and hook set
  4. clear solo cup
  5. dial calipers
  1.  Set up as shown.
  2. Place cup with water on the scale and then turn it on.
  3. Lower hooked steel block into the water and take a reading of weight of water displaced (~16.4g).
  4. Weigh the steel block (~127.7g).
  5. Divide the mass of the steel by the displacement weight of water to get the specific gravity (~7.8).
  6. Repeat process with other samples.
Using calipers, the volume of each cube has been found to be ~16.4 cm cubed.

 

Reaction Time Stick

Demo: ME-A-RT
Pira Index: 1A 20.60

 Lab Equipment  Directions
  1.  Specially marked meter stick
  1.  One person holds the meter stick vertically with the ‘0’ end down.
  2. The second person prepares to pinch it between his thumb and forefinger at the level marked ‘0’. The first person lets the meter stick drop.
  3. The point at which the meter stick is pinched indicates reaction time.

 

Radian Disk

Demo: ME-A-RD
Pira Index: 1A 50.10

 Lab Equipment  Directions
  1.  Radian disk on lab stand
  2. Large wooden protractor
  1.  Use the plastic strip on a string to show the measure of the radius.
  2. Bend the strip along the arc cut off by the indicated angle to show that a radian is defined as the angle that cuts off an arc equal in length tc the radius of the circle. Since the circumference = 2πr, then there are 2π radians in 360 degrees.

Geometric Function Cups

Demo: ME-A-GF
Pira Index: 1A 50.00

 Lab Equipment  Directions
  1.  7 stacks of styrofoam cups in holder (1, 2, 4, 8, 16, 32, 64 high)
  1.  Place each stack of cups in the holder, one at a time from the smallest stack to the largest stack.
  2. Observe the shape of a line graph that would be drawn across the top of the rows of cups.

 

Force Vectors

Demo: ME-A-FV
Pira Index: 1A 40.00

 Lab Equipment  Directions
  1.  sunbeam dial platform scale
  2. 2000g spring scale
  3. 2 – 2000g masses
  4. foam core board marked with angles
  5. 2×4 with hooks
  1.  Adjust the platform scale to a zero setting. Then set the masses on the 2×4 as shown on top of the scale. It should read approximately 4600g.
  2. Using a spring scale, pull on the side hook with a force of 700g, keeping the pull carefully aligned with the 45 degree line on the foam core board. Note the platform scale reading shows a loss of 495g. Show that by calculation the 700g pull has an upward component of 495g.
  3. Repeat with 30 degrees and 60 degrees alignments. (Have students calculate the expected results before trying the last 2 angles).