Some Hypotheses For Physical & Earth Sciences Labs
In each of the following examples, the dependent variable is red while the
independent variable is blue. These variables are identified in the if clause only,
however, you might want students to treat the variables in the same way in the then clause. Also,
each example given can be composed in a variety of ways. For example, there is nothing incorrect
with reversing the order of the independent and dependent variables. I just do it one way for
consistency. As far as the independent variable is concerned, it can be varied by increasing,
decreasing or removing it entirely. Finally, the two variables in question do not actually have to be
related. Observations from testing the independent variable will reveal the nature of the relationship
such as direct, indirect, limited range, or no relationship at all (as in the first example).
If the period of a pendulum is related to its mass, then increasing (or decreasing) the mass will increase (or decrease) the period. (actually no relationship)
If the velocity of sound is related to the density of the material conducting the sound, then increasing the density will increase the velocity.
If frequency is related to wavelength, then increasing the frequency will shorten the wavelength.
If current flow is related to resistance, then increasing the resistance will decrease the current.
If magnetism is related to electrical current, then the greater the current, the greater the magnetic field.
If potential energy is related to position, then an object furthest from the center of the earth will have more potential energy than an object that is closer.
If the volume of a gas is related to temperature, then increasing the temperature will increase the volume.
If the volume of a gas is related to pressure, then increasing the pressure will decrease the volume.
If pressure of a gas is related to temperature, then increasing the temperature will increase the pressure.
If solubility of a gas is related to temperature, then increasing the temperature will decrease the solubility.
If reaction rate is related to surface area, then increasing the surface of reactants will increase the rate of reaction.
If reaction rate is related to temperature, then increasing the temperature of the reactants will increase the rate of reaction.
If air temperature is related to air pressure, then increasing altitude will decrease temperature.
If climatic temperature is related to absorption of solar energy, then increasing latitude will decrease the average climatic temperature.
If climatic temperature is related to the specific heat of matter, then the more distant a location is from large bodies of water, the more quickly the climatic temperature will change with the seasons.
If sedimentation is related to particle size, then particles which settle out of water will sort themselves from large to small.
If sediment load is related to water velocity, then the slower the water, the less sediment it will contain.