What is the Problem
A builder uses a blue light scan the toilet and plumbing lines in a bathroom. Why is this technology useful?
The blue light will "glow" whenever it reflects of any water helping the builder find water leaks around the plumbing lines and toilet
A student conducts an investigation using engineering design process to use solar panels to run a full scale SUV. Which of the steps below apply to the process:
A) Write an hypothesis
B) Use a model to test a solution to the problem
C) Evaluate solutions against the problem definition
D) Establish the test criteria using dependent and independent variables
E) Formulate questions and seek answers in a systematic way
F) Perform calculations (make a math model) to predict energy generated from a new material not used in solar panels before
B and C
Name one example of a technology and one example of a natural system in the classroom
1) any technology
2) any living organism
A box car derby car made it's first test run and completed the run in 2 minutes. After improvements, it completed the second run in 1 minute 46 seconds. What was the percent improvement of the second run compared to the first
14 second improvement divided by 120 seconds of the first run equals 11.7% improvement.
Using the system diagram of a house off the grid at the link below:
The input of the wind turbine is?
Wind
In our aquarium, we measure for nitrites and nitrates which are produced by the excretions from the fish. Why is it important to study and understand the system interactions in our aquarium ecosystem?
This information helps us understand the relationship between the quality of the water and the health of the fish.
Look at the data in the table at the link below:
https://docs.google.com/spreadsheets/d/1EvwtZIWZ-ZmFDKPZcMLpaZn7XjE6qdbpRb__VHM45DE/edit?gid=0#gid=0
If the design had a constraint that it had to meet 35% relative in 60 minutes or less for a 300 sqft room, pick which answer is best:
A) The dehumidifier did NOT meet the constraint.
B) The dehumidifier DID meet the constraint.
C) The test is invalid because it was done on the wrong size room.
D) The dehumidifier did meet the constraint because I can infer that because it almost met the requirement in a larger room, it would meet the requirement for the smaller room.
C)
Science influencing technology or technology influencing science. Which is the following example:
The fundamental principles of electro magnetism led to the development of the electric motor, the transformer and radio communications.
Science influencing technology
Using the graph at the link below:
https://docs.google.com/spreadsheets/d/1EvwtZIWZ-ZmFDKPZcMLpaZn7XjE6qdbpRb__VHM45DE/edit?gid=0#gid=0
Interpret what the relative humidity was at 30 minutes
56% (acceptable answers range from 58% to 54%
Using the system diagram of a house off the grid at the link below:
The input and output of the batteries is?
Electricity
An engineer has created a new pen that must write upside down with fluorescent ink that glows in the dark. He tests it many times at various orientations and light levels. What is this testing called and why does he do it.
Iterating testing. It allows the engineer to ensure that the design meets the criteria and constraints of the problem and improve the design if it does not.
After choosing a possible solution based on your scoring of the criteria and constraints against the various options, your next step is?
Design and build a prototype
Science influencing technology or technology influencing science. Which is the following example:
The creation of the Hubble telescope led to the concept of dark matter
Technology influencing science
Using the table at the link below:
https://docs.google.com/spreadsheets/d/1EvwtZIWZ-ZmFDKPZcMLpaZn7XjE6qdbpRb__VHM45DE/edit?gid=0#gid=0
What was the average drop in percent per 5 minutes for the relative humidity between 0 and 20 minutes
The RH dropped 12% (82 to 70) during the 20 minutes from 0 to 20. The average drop must be per 5 minutes, so the equation is 12% divided by (20 minutes/5 minutes) = 12% / 4 = 3% per 5 minute average
Using the system diagram of a house off the grid at the link below:
The purpose of the Dump load is?
A) Remove excess electricity from the system
B) Allow for additional storage of electricity not used by the house
C) Convert the electricity to waste to feed the plants outside
D) Cool the house
A
Two part Question:
1) What step does the engineer do at the beginning of the Engineering design process?
2) What is the next step?
1) Identify the problem or need.
2) Determine the criteria and constraints for the potential solution
A foreign country begins restricting the supply of oil that is exported to the United States to cause a rise in gasoline prices. As a result, citizens begin reducing driving, and manufactures produce more fuel efficient cars or cars that run on electricity. This is an example of ________________ influencing ____________. Explain.
society influencing technology. The higher prices caused society to seek alternatives including new technology that used less or no gas.
Look at the Google Sheet Weather Circulation and Stream Runoff at this link: https://docs.google.com/spreadsheets/d/14EfRyL-wmsvYVpcbvX0CV-CxR2pV5u1l49sEYrYDCpQ/edit?gid=1982537474#gid=1982537474
Number the events in the correct order
5, 2, 1, 3, 4
What is the slope of the line from 10 minutes to 20 minutes in the graph (give answer in percent per minute) at:
https://docs.google.com/spreadsheets/d/1EvwtZIWZ-ZmFDKPZcMLpaZn7XjE6qdbpRb__VHM45DE/edit?gid=0#gid=0
The RH drops from 70% to 62% or -8% and the x axis changes by 10 minutes therefore the slope is -8% per 10 minutes or -0.8% per minute.
Using the system diagram of a house off the grid at the link below:
If the output of the dump load is heat, how might the output be used around the house?
Heat water for showers, baths, heat the house, use for energy to make steam for alternate energy source. (Any answer that demonstrates heat use)
Moira has an electric bike. The bike has two modes: 1) it provides power to the hub to assist her when riding (assisted work), or 2) it takes power from the hub to recharge the battery but she must peddle much harder. What will happen if she never uses the second mode?
The second mode provides additional energy for the system to perform work. If she never uses it, there will be less overall energy available for work
If a potential solution meets all of your criteria and has the best overall score in your analysis but fails one of the constraints, you should?
Ignore it or redesign to meet the constraints. Constraints are limits that must be met and therefore you cannot continue with this solution even though it scored the best in your analysis.
You are thinking about making a solar still that would help you collect water from moist ground. You would like it to make about 12 ounces of water and can carry an extra 5 pounds of materials to assemble the still. Since you have a problem statement with criteria, what is your next step?
Researching ideas to come up with possible solutions
I want to build 10 robots for the robot challenge in class. Each robot costs $25.50. I have $200 and 100 chocolate bars. How much would I have to sell 50 chocolate bars in order to have enough money for the robots?
Amount needed: 10 * 25.5 or $255. We have 200 so we need ($255 - $200) = $55 more. We need $55 dollars and are willing to sell 50 chocolate bars to get it so $55 divided by 50 = $1.10 per bar.
The output of the charge controller is Direct Current (DC power) which is required for battery storage and is also input to the off grid inverter. The output of the grid inverter goes to the house which shows that it's input is single phase alternating current (single phase AC). What can we surmise in the purpose of the grid inverter by this relationship?
The grid inverter converts DC power to single phase AC power.