Gravity vs. Mass

Question? How does mass affect gravity?

Answer: The difference in the mass of objects determines which will win in a gravity tug-of-war between them. The mass of Earth is 5.97 x 10²⁴ kg.

Question: What is gravity?

Answer: The basic answer to this question is that gravity is a force that pulls things toward the center of the Earth.

The diagram represents the tug-of-war between the Earth and a rock. The size of the arrows indicates the strength of the tugging force for each object. Note that the arrow pointing toward the Earth is much larger than the arrow pointing toward the rock. Certainly looks like the Earth is going to win this battle.

Did You Know?

Gravity is a force of attraction between all the objects in the universe. Yep! This means that your body is in a tug-of-war with everything around you. Thankfully, gravity is a very weak force. If it was stronger, objects would start flying toward you and of course you would start flying toward stuff. YIKES!!! This would be a real mess.

Question: Why is the gravity of Earth so much greater than the gravity of other things, such as people, animals, rocks, etc…?

Answer: The difference in the mass of objects determines which will win in a gravity tug-of-war between them. The mass of Earth is  5.97 x 10²⁴ kg.

Did You Know?

1. Mass is the amount of matter that something is made up of. In other words, your body mass is all the atoms that make up your body.

2. When a number is multiplied by 10 to a power, such as 10²⁴ , this mean the number is multiplied by 10 twenty four times, or that the decimal place is moved to the right twenty four places. If we write out the number 5.97 x 10²⁴ kg, it would look like this: 5,970,000,000,000,000,000,000,000 kg.

Now you know why Earth is a champion at  tug-of-war.

Challenges: What about the Moon? What about asteroids in space? YIKES! Is Earth pulling the whole universe down on us? Who will be the final winner? Isn’t the Sun more massive than the Earth? What is keeping the Earth from being drawn into that fiery infernal?

Tune in tomorrow for more up-to-date news about the ongoing  Universal tug-of-war tournament.

Janice VanCleave’s Gravity: Spectacular Science Projects