Students want to design an experiment to study gravity. They decide they will drop four objects with the same mass from the top of their school’s bleachers. They will time how long each object takes to reach the ground. How can they improve confidence in the experiment’s results?

Question

Responses

Let a different student time the drop of each object.
Let a different student time the drop of each object.

Drop each object 10 times and use the average of each object’s fall times.
Drop each object 10 times and use the average of each object’s fall times.

Randomly select the order in which the objects are dropped.
Randomly select the order in which the objects are dropped.

Drop all four objects at once.

Answer 1

To improve confidence in the experiment's results, the most effective approach from the responses provided is:

Drop each object 10 times and use the average of each object’s fall times.

This method accounts for variability in timing due to human error, environmental factors, or other inconsistencies, providing a more reliable measure of how long each object takes to fall, leading to more accurate comparisons of their fall times.

While the other suggestions—having different students time the drops, randomly selecting the order of drops, and dropping all objects at once—can also help reduce some variables, averaging multiple trials is a widely accepted practice to enhance the reliability of experimental results.