Exploring scientific method: hypothesis, variables and graphing

 

Activity 1:  Hypothesis and Variable Practice

Directions: For each of the scenarios below answer questions A-C.

 

  1. Identify the Independent Variable (IV), Dependent Variable (DV), Standardized or Controlled Variable (SV), the number of repeated trials, and the control setup (if present).
  2. Identify the Hypothesis for the experiment. If the hypothesis is not stated, write one for the scenario.
  3. Identify 2 ways the experiment can be improved.

 

Scenario 1: Gloria wondered if the height of a hole punched in the side of a quart sized milk carton would effect how far from the container a liquid would spurt when the carton was full of liquid. She used 4 identical cartons and punched the same size hole in each. The hole was placed at a different height on one side of each of the containers. The height of the holes varied in increments of 5 cm, ranging from 5 to 20 cm from the base of the carton. She blocked the holes with her finger and filled the cartons to a height of 25 cm with water. When each carton was filled to the proper level, she placed the cartons on the edge of the sink and removed her finger. Gloria measured how far away from the cartonís base the water had squirted when it hit the bottom of the sink.

 

Scenario 2:  Sam wanted to find out if the color of food would affect kindergarten children lunch selections. Sam put food coloring into 4 identical bowls of mashed potatoes. The colors were red, green, yellow, and blue. Each child would choose the color of their choice. Sam did this experiment using 100 children. He recorded the selection color for each student.

 

Activity 2: Graphing

  1. Collect class data for age, gender and height. Do this in your journal, use a ruler for the data table. Remember the independent variable of manipulated variable affects the dependent variable or the responding variable. (Placing the I.V in the left column of a data table and the D.V. in the right column is a good method to use.)
  2. Construct a graph which will allow you to predict the height of a person at age 5, 10, 15 and 20. Remember to follow graphing rules. X axis is the I.V. and the Y axis is the D.V..
  3. According to your graph, what are the average heights for a 5 year old _______, 10 year old ______, 15 year old _______ and a 20 year old________?
  4. Would separating gender give a more accurate prediction? __________ Why? ________________________________
  5. Staple your Excel Graph to this paper.
  6. If your teacher had you do both a hand drawn graph and an excel graph. Answer the questions for the excel graph: According to your graph, what are the average heights for a 5 year old _______, 10 year old ______, 15 year old _______ and a 20 year old________?
  7. Would separating gender give a more accurate prediction? __________ Why? ________________________________