Section 10 of 9
In Progress

Gravity Free Fall

Approximate time to complete: 10-15 minutes + questions and journal time

Experiment Card

Click below to download and print this experiment card:

Purpose

All objects have a gravitational force that attracts other objects. It can really only be noticed when very large objects act on comparably small objects: the Sun keeping the Earth in orbit, the Moon pulling on the water in the oceans to make the tides, or the Earth pulling us down onto the surface. Let’s demonstrate the effect of gravity here on Earth.  

Materials

  • Paper Cup
  • Bathtub or Sink to Catch Water (this can also be done outside)
  • Large Cup Filled with Water
  • Video Recording Device + Helper (optional)
  • Scissors or Knife

Safety Considerations

Ask an adult for help before using scissors, knives, or any other sharp objects needed in this experiment.

Procedure

Do this demonstration over the bathtub / sink, or go outside to do it.

  1. Poke a hole in the side of the paper cup.
  2. Cover the hole with your finger.
  3. Fill the cup with water.
  4. Take your finger off of the hole. What happened to the water?
  5. Repeat steps 2 and 3.
  6. If you have a helper and a video recording device, record the next step.
  7. Drop the cup. What happened to the water while the cup was falling?
    • Try this a few times, or re-watch your video in slow motion if possible.

Questions & Further Research

  1. What happened to the water when you removed your finger? Did it stay in the cup?
  2. What happened to the water when you dropped the cup? Did it come out of the cup?
  3. Did gravity pull the cup down faster, the water down faster, or pull them at the same speed? What does that tell us about how gravity affects objects?

Hint

  • When you take your finger off of the hole, gravity pulls the water down towards Earth, and out of the cup. 
  • When you drop the cup, gravity pulls the water AND the cup down towards Earth at the same speed. Since water is already taking the easiest path (straight down) it does not need to move out of the cup to get where gravity wants it to go.