Gravity: Will the Water Leak Out Science Experiment

What if I told you that you could poke a hole in a cup, pour water into the cup, and the water would not leak out? It doesn’t seem possible, does it? In this easy science experiment, we’re going to use science to show us that it is and tell you why!

Collect your supplies (including a video recorder, if possible), watch our demonstration video, and explore how gravity is the secret behind both water leaking out of a cup and NOT leaking!

JUMP TO SECTION: Instructions | Video Tutorial | How it Works | Purchase Lab Kit

Supplies Needed

• Styrofoam Cup
• Paper Clip or Push Pin
• Water
• Large Container
• Video Recorder (optional)

Water Doesn’t Leak Out Science Experiment Instructions

Step 1 – Use the end of a paper clip or a pushpin to poke two holes in the cup. The holes should be on opposite sides of the cup and about an inch from the bottom.

Step 2 – Next position the cup, so your fingers are covering the holes, and fill the cup with water.

Step 3 – Holding the top of the cup, remove your fingers from the holes, and observe what happens. The water will begin to leak out of the holes.

Step 4 – Again, position the cup, so your fingers are covering the holes, and fill the cup with water. This time, hold the cup high in the air above a large container. Drop the cup and watch carefully as it falls into the container. As it is falling you will notice that the water does not leak out of the holes.

Helpful Tip: Record the experiment and then watch it in slow motion to better observe the experiment.

Do you know why the water doesn’t come out of the holes while the cup is falling? Find out the answer in the how does this experiment work section below.

Video Tutorial

Why Doesn’t the Water Leak out of the Holes Science Experiment

How Does the Science Experiment Work

Gravity is the secret to this experiment! Gravity is a force that pulls objects towards Earth, and towards other objects with a similar mass. Gravity causes all objects to fall, and all objects fall at the same rate if air resistance is the same {Source}.

Gravity is the reason the water leaks out of the holes when you hold the cup in Step 3. Gravity is pulling the water (and cup) back to Earth, so the water takes the path of least resistance back to Earth – out of the holes.

Gravity is also the reason water doesn’t leak out of the holes when you drop the cup in Step 4. In this step, gravity is still pulling the water back to Earth, but this time the cup and water are falling back to Earth at the same rate when you drop the cup. This doesn’t allow water to leak out of the cup because the water is already taking the path of least resistance back to Earth – straight down with the cup.

Science Fun Facts

You weigh about 6 times more on Earth than you would on the moon. This is because the moon has weaker gravity. {Source}

I hope you enjoyed the experiment. Here are some printable instructions:

Water Doesn’t Leak Out Science Experiment

Print

Materials

• Styrofoam Cup
• Paper Clip or Push Pin
• Water
• Large Container
• Video Recorder (optional)

Instructions

1. Use the end of a paper clip or a push pin to poke two holes in the cup. The holes should be on opposite sides of the cup and about an inch from the bottom.
2. Next position the cup, so your fingers are covering the holes, and fill the cup with water.
3. Holding the top of the cup, remove your fingers from the holes and observe what happens. The water will begin to leak out of the holes.
4. Again, position the cup, so your fingers are covering the holes, and fill the cup with water. This time, hold the cup high in the air above a large container. Drop the cup and watch carefully as it falls into the container. As it is falling you will notice that the water does not leak out of the holes. Helpful tip: Record the experiment and then watch it in slow motion to better observe the experiment.