Experimental Design B/C

[dxu46]

You conduct an experiment studying the rate of diffusion of particles in different liquids, such as water, saltwater, and lemonade. Describe some possible applications.

Possible Answer (Click to Show Hidden Text)

An application for this experiment is that some companies who want to dispose of potentially difficult to carry objects can use the results of this experiment to find out which solvent dissolves which solute the fastest to save time and/or work.

^ Yes, I know that this is highly improbable, but there's nothing in the rules about this being very realistic

[UTF-8 U+6211 U+662F]

You conduct an experiment studying the rate of diffusion of particles in different liquids, such as water, saltwater, and lemonade. Describe some possible applications.

Possible Answer (Click to Show Hidden Text)

An application for this experiment is that some companies who want to dispose of potentially difficult to carry objects can use the results of this experiment to find out which solvent dissolves which solute the fastest to save time and/or work.

^ Yes, I know that this is highly improbable, but there's nothing in the rules about this being very realistic

Try again. Diffusion is not the same thing as dissolution

[dxu46]

You conduct an experiment studying the rate of diffusion of particles in different liquids, such as water, saltwater, and lemonade. Describe some possible applications.

Possible Answer (Click to Show Hidden Text)

An application for this experiment is that some companies who want to dispose of potentially difficult to carry objects can use the results of this experiment to find out which solvent dissolves which solute the fastest to save time and/or work.

^ Yes, I know that this is highly improbable, but there's nothing in the rules about this being very realistic

Try again. Diffusion is not the same thing as dissolution

Well, since dissolution causes diffusion (e.g. block of sugar turning into sugar particles which move from high to low concentration), one could argue that these two topics are related, and the answer above is applicable.

[UTF-8 U+6211 U+662F]

Possible Answer (Click to Show Hidden Text)

An application for this experiment is that some companies who want to dispose of potentially difficult to carry objects can use the results of this experiment to find out which solvent dissolves which solute the fastest to save time and/or work.

^ Yes, I know that this is highly improbable, but there's nothing in the rules about this being very realistic

Try again. Diffusion is not the same thing as dissolution

Well, since dissolution causes diffusion (e.g. block of sugar turning into sugar particles which move from high to low concentration), one could argue that these two topics are related, and the answer above is applicable.

Shrug. That's kind of pushing it, especially since the experiment conducted may or may not have used particles soluble to all the liquids given, but sure. Your turn.

[dxu46]

Bob wonders how being in a swimming pool for an extended amount of time affects body weight. He decides to test this experiment using IV levels of 20 minutes, 40 minutes, and 1 hour.
a. Write a hypothesis for this experiment.
b. List materials and write a condensed procedure for this experiment.
c. Identify and explain one possible experimental error in this experiment.

[Jacobi]

Bob wonders how being in a swimming pool for an extended amount of time affects body weight. He decides to test this experiment using IV levels of 20 minutes, 40 minutes, and 1 hour.
a. Write a hypothesis for this experiment.
b. List materials and write a condensed procedure for this experiment.
c. Identify and explain one possible experimental error in this experiment.

Answer (Click to Show Hidden Text)

a. Being in a swimming pool for a longer period of time causes a greater decrease in body weight because the chlorinated water causes osmosis through the skin.

b. Materials: 3 humans, 1 complete swimming pool system, 3 bathing suits, scale

Procedure:
1. On Day 1, have human A put on his bathing suit and weigh him.  Record the weight.  
2. Have him sit in the pool for 20 minutes.  
3. After twenty minutes, call him out and weigh him again.  Record the weight.
4. Calculate the difference between the weights recorded in #1 and #3 and record it.  
5. Wait for the water to cycle through.
6. Repeat 1-5 for humans B and C.
7. On Day 2, repeat 1-6 for a forty-minute interval.
8. On Day 3, repeat 1-6 for a 1-hour interval.

c. One possible experimental error could be behavior overnight.  Although this interval is necessary to have the subjects return to their natural weight, their behaviors could differ significantly on Night 1 versus Night 2.

[dxu46]

Bob wonders how being in a swimming pool for an extended amount of time affects body weight. He decides to test this experiment using IV levels of 20 minutes, 40 minutes, and 1 hour.
a. Write a hypothesis for this experiment.
b. List materials and write a condensed procedure for this experiment.
c. Identify and explain one possible experimental error in this experiment.

Answer (Click to Show Hidden Text)

a. Being in a swimming pool for a longer period of time causes a greater decrease in body weight because the chlorinated water causes osmosis through the skin.

b. Materials: 3 humans, 1 complete swimming pool system, 3 bathing suits, scale

Procedure:
1. On Day 1, have human A put on his bathing suit and weigh him.  Record the weight.  
2. Have him sit in the pool for 20 minutes.  
3. After twenty minutes, call him out and weigh him again.  Record the weight.
4. Calculate the difference between the weights recorded in #1 and #3 and record it.  
5. Wait for the water to cycle through.
6. Repeat 1-5 for humans B and C.
7. On Day 2, repeat 1-6 for a forty-minute interval.
8. On Day 3, repeat 1-6 for a 1-hour interval.

c. One possible experimental error could be behavior overnight.  Although this interval is necessary to have the subjects return to their natural weight, their behaviors could differ significantly on Night 1 versus Night 2.

Corrections (Click to Show Hidden Text)

a. Technically, it's correct, but I'd prefer it to be in the form of If...then...because... but cause-effect works I guess.
b. Procedure: You forgot to include "Record data etc."
c. That's fine, although you forgot to include type of error.

Your turn.

[Jacobi]

Design an experiment on the topic: projectile motion. Use these materials: 3 marbles of different weights, stopwatch, ruler, table.

[dxu46]

Design an experiment on the topic: projectile motion. Use these materials: 3 marbles of different weights, stopwatch, ruler, table.

Click to Show Answer

SoP: How does weight affect projectile motion?

Hypothesis: If marbles of different weights are rolled down a ruler ramp, then they will travel farther the heavier their weights are because of Newton's 2nd law - F = M x A.

That satisfies the question?

[UTF-8 U+6211 U+662F]

Design an experiment on the topic: projectile motion. Use these materials: 3 marbles of different weights, stopwatch, ruler, table.

Click to Show Answer

SoP: How does weight affect projectile motion?

Hypothesis: If marbles of different weights are rolled down a ruler ramp, then they will travel farther the heavier their weights are because of Newton's 2nd law - F = M x A.

That satisfies the question?

Wait what do ramps have to do with projectile motion? Projectiles are only affected by gravity (and to a lesser extent, air resistance).