Hypotheses
What is a hypothesis?
An educated guess about what the scientist thinks will happen in the experiment.
If _____(an independent variable)_______, then ______(a dependent variable)_______
The _______________ is the thing that is measured. It is the change that happens as a result of something else. It comes from the data collected.
Dependent variable
How many tablespoons of salt were added for the object to float the highest?
3 tablespoons
If you want to test how different ramp heights affect how far a toy car travels, what should your scientific question be?
How does ramp height affect how far a toy car travels?
Ms. Yousuf tested how high five different brands of new tennis balls would bounce when dropped from a height of 2 meters. She dropped the balls so that they would hit the same floor tile each time. What are 2 constants?
height of the drop, type of floor
What is the format for a hypothesis?
If _____(an independent variable)_______, then ______(a dependent variable)_______
Ms. Bean wanted to test how the amount of light affected plant growth in a classroom. She put the same type of seedling in different light conditions and measured growth over time.
What is the dependent variable
The plant heights
Which materials were insulators?
plastic and rubber
What is the format for a scientific question?
How does _____(independent variable)___ affect _____(dependent variable)_______
A scientist uses _____________ to make sure that the results of the experiment and valid and occur again.
repeated trials
Students compare temperatures black, white, purple, and red surfaces in sunlight. What should the hypothesis be?
If the surface is black, then it will heat up faster.
Students add different amounts of salt to cups of water and test whether an egg will float.
What is the independent variable?
The amount of salt in the water
Which plant grew the tallest?
The plant that was given 30 mL of water
Ms. Joyce adds different amounts of salt to cups of water and tests whether an egg will float. What is her scientific question to guide this experiment?
How does the amount of salt in water affect how well an object floats?
Determine if Ms. Bean's hypothesis is supported by the data. Ms. Bean thought that people would be able to taste small amounts of sugar more easily than vinegar or salt. She found that people could detect 2 mL of salt per liter of water, 1.5 mL of sugar per liter of water, and 0.5 mL of vinegar per liter of water. Explain if her hypothesis was supported or not.
It was not supported because a smaller amount of vinegar was detected in the same amount of water.
Ms. Yousuf is testing different kinds of markers to see which will last longer. She tests Crayola, Rose Art, and Target markers. Based on her past experience, she thinks Crayola markers will last the longest. How should she write her hypothesis?
If I use Crayola markers, then they will last the longest.
Ms. Yousuf is testing different kinds of markers to see which will last longer. She tests Crayola, Rose Art, and Target markers. She used a thick red marker of each type and colored for 15 minutes with each marker. At the end of the 15 minutes, the Target marker was making pink lines, the Rose art marker was making thin red lines, and the Crayola marker was making thick red lines. What are 2 constants in this experiement?
The amount of time coloring with each marker
The size of the markers
How much more soil was washed away when the slope of the hill was 40 degrees compared to when the slope of the hill was 10 degrees?
20 grams
Mr. Coleman is doing an experiment. This is his hypothesis: If an object is closer to the light source, then its temperature will increase. What was his scientific question?
How does distance from a light source affect temperature?
Ms. Yousuf is testing different kinds of markers to see which will last longer. She tests Crayola, Rose Art, and Target markers. She used a thick red marker of each type and colored for 15 minutes with each marker. At the end of the 15 minutes, the Target marker was making pink lines, the Rose art marker was making thin red lines, and the Crayola marker was making thick red lines. What is the independent variable?
Type of marker
Ms. Bean wanted to test how the amount of light affected plant growth in a classroom. She put the same type of seedling in different light conditions and measured growth over time. Based on what she knows about plants, what should her hypothesis be?
If plants receive more sunlight, then they will grow taller.
Mrs. Contreras wanted to know which material was the best conductor in a simple circuit. She tested different materials in a circuit to see whether the bulb lit up brightly, dimly, or not at all. What are 3 constants she should have in her experiment?
Same battery, same bulb, same wire setup
What happened to the toy car as the ramp height increased?
The car traveled a further distance
Mrs. Contreras is doing an experiment. This is her hypothesis: If the listener moves farther from the sound source, then the sound will seem quieter because sound energy spreads out.
What is her scientific question?
How does distance affect how loud a sound seems?
Look at the graph. What is the dependent variable?
temperature