Group Lab II: Water Flow

Hydrostatic Water

In our second group lab we studied hydrostatic water. What we wanted o figure out was how long it would take for the water to flow through different sized holes at the bottom of a cylindrical container.

What We Need to Figure Out
Velocity
Volumetric flow rate

Materials
A bucket
Two stable surfaces (notebooks) for containers to balance on
3 Cylindrical containers (empty soups cans with lids removed), label as 1, 2, and 3
Drill with 3 different sized drill bits
Ruler
Stopwatch
Marker

Steps
(The containers were pre-drilled and marked for us)
1. Measure and record diameter of the bottom of the can
2. Drill a hole through the center of the bottom of the can
3. Mark the inside of each can with a line, 3 inches from the bottom
4. Place the soup cans next to each other on the bucket leaving a gap for water flow through
5. Cover the hold of your 1st can with your finger and fill to the marked line
6. Remove finger as you place can on notebooks on buckets, with the hole above the gap
7. Measure the time it takes for the water in the can to deplete.
8. Record data and repeat steps with rest of cans

 

Results

Here is a chart of our collected data

Here is a chart for out analyzed data

What we observed was that as the size of the hole in each can increases so does the average velocity of the water flow as listed in the chart. Can 3, which had the largets hole, hda the greatest avergae velocity followed by 2 then 1.


Group Lab I: Heat and Insulation

Heat Conservation Using Coffee Cups

In recent years coffee distributors have been coming up with products or materials that are supposed to keep our cups of coffee hotter longer. From the cardboard sleeve to the foam koozie, this experiment aims to find which one holds up to the test.

These heating methods, if they work, can be applied on a much broader level. In our current approach to insulating houses to preserve heat, we use fiberglass insulation. However, this process is not sustainable. The goal of this experiment is to come up with the best and most sustainable alternative to fiberglass insulation.

 

Materials
Hot water (enough to fill each cup)
6 plastic coffee cups with straw-friendly lids
2 cardboard coffee cup sleeves
1 koozie sleeve
1 piece of denim
1 ft. of plastic wrap
1 ft. of aluminum foil
6 thermometers to be placed through the straw hole of each cup
1 timer

 

Steps
1. (Coffee cups were pre-wrapped for our convenience)
2. Fill cups with hot water and immediately cover and input thermometers
3. Document starting temperature of each cup
4. Repeat after 10 minutes
5. Repeat after 20 minutes
6. Repeat after 30 minutes

 

Results

 


Preservationists of Heat (Best to Worst)
Aluminum Foil: -12°C
Denim: -13°C
Plastic Wrap: -15°C
Koozie: -15°C
Cardboard: -17°C
Original Cup: – 19°C

 

In our version of the experiment, foil preserves the most heat of each insulating medium. This was not the expected result. Considering our starting point for the foil insulation was much lower than those of the others, there is a possibility that we misread the thermometer by a couple degrees.

But with our results as they are, foil is the best insulator of the ones presented.


Energy in Motion

(L to R: Donny Barnas, Erik Storer, Nancy Afonso, Nixandra McGuffie)

Purpose of the Experiment
Our objective is to examine the relationship between energy and a moving object

Objective
Determine the effect of releasing a ball from different heights on a ramp affects the potential and kinetic energy of the ball. Find how manipulating height affects potential energy and ball’s ability to break through obstacles. Furthermore, we want to find how many joules of energy tissue and foil can withstand before ripping.

Questions
1. At which angle of the ramp in relations to the ground will produce the greatest level of velocity?
2. What is the maximum amount of gates each ball is capable of penetrating?
3. How does the size/weight of the four different balls affect their end results?
4. Does changing the height or starting distance of the balls significantly affect the end result of broken gates, if so how?

Materials
1 weighted ball (60g)
Adjustable, metal curtain rod (used as ramp). We cut off one curved end of the rod to make our ramp linear
Tape Measure
Tin foil and tissue paper (used as gate sfor ball to break through)
Stop Watch

 

 

 

 

Weighted Sphere/Ball

Curtain Rod used as ramp

Principles
The main principles tested in our experiment are potential energy, kinetic energy, and velocity.

Potential Energy: The energy possessed by a body as a result of its position or condition rather than its motion. In our experiment, potential energy is the energy of the ball before it is released down the ramp. As the height of the ramp increases so does the gravitational potential energy of the ball allowing the ball to covert more potential energy to convert to kinetic energy as it rolls down
Potential Energy = Mass x Gravitational Acceleration x Height

Kinetic Energy: The energy possessed by a system or object as a result of its motion. Kinetic energy is dependent on two variables: mass and velocity of the object. As the ball rolls down the ramp potential energy will be converted to kinetic energy.
Kinetic Energy = ½ x Mass x Velocity^2

Velocity: The rate and direction of the change of an object or simply speed in a given direction. The distance traveled by the ball from the top of the ramp to its destination point over the time spent to reach that point.
Velocity = Distance / Time

Procedure
1. Measure length and height of rod
2. Calculate Potential Energy
3. Place tissue/foil at end of rod
4. Hold ball in starting position and release
5. Calculate Velocity and Kinetic Energy
6. Document other findings (i.e. did ball break through tissue paper/foil)

 

 

 

Results

From years of nose blows ripping through our tissues, our group reasoned that with tissue’s minimal density, the ball would have a better chance of rolling through the paper. This is because its lesser density would require less energy of the ball.

Our results proved us right. The ball was able to rip through the tissue when potential energy was at 0.104 Joules whereas the ball did not break through the foil until potential energy reached 0.224 Joules.

 

Here is a chart and graph of our data:

 

 

As shown in the above graph and chart, the “gates” broke when potential was at its highest. This is because height is a major component of potential energy. As height increases so does potential energy needed for the ball to break through.

Kinetic energy remained constant during all trials because the mass of the ball was unchanging (.06kg or 60g) and it traveled the same distance in the same amount of time, velocity (1.38m/s). This means that the ball’s potential energy in this experiment is the most determining factor of the ball breaking through the tissue/foil.

 

Questions Answered

Q: What was the lowest height that will cause a break in the tissue and tinfoil?
A: For our 60g ball test the minimum height was 0.17m for tissue and 0.38m for foil

Q: How many joules did each of these heights equate to for potential energy?
A: For the tissue 0.104J and for the foil 0.224J was required.

Q: How does the size/weight of the four different balls affect their end results?
A: Discuss after class activity.

Q: Did you notice the potential energy increased or decreased in relation to height?
A: As height increased the P.E. also increased

Q: Does changing the height or starting distance of the ball significantly affect the end result of breaking the gate, if so how?
A: The higher the ball the more joules are present providing enough velocity to eventually penetrate the gate subjective to starting height.

 

From our experiment we could rewrite the age old saying to the higher they are the harder they fall.