Ask:
What is a model?
A model represents the real thing.
What functions or properties should our model membrane have?
holes.
What are the constraints on our design?
limited water, habitat, not too much water.
What materials might be good choices for designing a model membrane?
sponge, felt, coffee filter, tinfoil.
How can we determine if the materials are useful in designing a model membrane?
Test out different materials to see if the water goes through at a good rate.
Let's test our materials!!
What did we find out?
Sponge:
Amount of water: some
Rate: medium
observations: When you're done pouring it goes slower since there is no pressure.
Tin Foil
Amount of water: none
Rate:slow
Observations: Tin foil needs to be placed correctly covering the entire cup otherwise water goes through.
Tin Foil w/ 1 hole
Amount of water: depends on the size of the whole
Rate: depends on the size of the whole
Observations: It went quickly when it started going towards the hole- like a funnel, went one drop per second (small hole)
Tin Foil w/ 2 holes
Amount of water: some
Rate: quickly
Observations: came out in two fast skinny streams, at the end (last 5 seconds) only one hole was dripping, when 3 drops a second, before 30 seconds water was out, 1 hole had a thick stream and one skinny, One small and one medium hole and the small hole drips small, medium drips a river
Felt
Amount of water: all
Rate:quickly
Observations: within first 3 seconds water was through, it went straight through- that was different than we thought.
10 coffee filters
Amount of water: some
Rate:medium
Observations: started off slow then got quicker
Cheesecloth
Amount of water: all
Rate:quickly
Observations: All went through as we poured
Screen
Amount of water: all
Rate:quickly
Observations: all gushed out even when we stopped pouring, some drips got stuck kon screen.
We think the best was....
Aluminum foil with 1 hole... good rate, sponge because it went one drop of a time, Aluminum with 1 hole good rate, coffee filters, One hole tin foil..........
What is a model?
A model represents the real thing.
What functions or properties should our model membrane have?
holes.
What are the constraints on our design?
limited water, habitat, not too much water.
What materials might be good choices for designing a model membrane?
sponge, felt, coffee filter, tinfoil.
How can we determine if the materials are useful in designing a model membrane?
Test out different materials to see if the water goes through at a good rate.
Let's test our materials!!
What did we find out?
Sponge:
Amount of water: some
Rate: medium
observations: When you're done pouring it goes slower since there is no pressure.
Tin Foil
Amount of water: none
Rate:slow
Observations: Tin foil needs to be placed correctly covering the entire cup otherwise water goes through.
Tin Foil w/ 1 hole
Amount of water: depends on the size of the whole
Rate: depends on the size of the whole
Observations: It went quickly when it started going towards the hole- like a funnel, went one drop per second (small hole)
Tin Foil w/ 2 holes
Amount of water: some
Rate: quickly
Observations: came out in two fast skinny streams, at the end (last 5 seconds) only one hole was dripping, when 3 drops a second, before 30 seconds water was out, 1 hole had a thick stream and one skinny, One small and one medium hole and the small hole drips small, medium drips a river
Felt
Amount of water: all
Rate:quickly
Observations: within first 3 seconds water was through, it went straight through- that was different than we thought.
10 coffee filters
Amount of water: some
Rate:medium
Observations: started off slow then got quicker
Cheesecloth
Amount of water: all
Rate:quickly
Observations: All went through as we poured
Screen
Amount of water: all
Rate:quickly
Observations: all gushed out even when we stopped pouring, some drips got stuck kon screen.
We think the best was....
Aluminum foil with 1 hole... good rate, sponge because it went one drop of a time, Aluminum with 1 hole good rate, coffee filters, One hole tin foil..........