Gravity

Objectives:

The students will be introduced to the concept of gravity.

They will learn that gravity is an invisible force that holds the solar system together.

Materials:

tape

long piece of string

tennis or rubber ball

computer with Internet

Activities:

Tell the story of Sir Isaac Newton and the apple tree. Teachers can visit PBS  and Sir Isaac Newton  for background information on Sir Isaac Newton.

Explain that he connected the force that kept the moon in orbit around the Earth with the force that made the apple fall.

Introduce the word "gravity" and explain what it means. Gravity is the tendency of matter toward some attracting body, particularly toward the center of the earth or other large body in space.

Next, have the students try to overcome gravity by jumping.

Ask: Why don't you fly off into space? Accept answers.

Next have one student jump holding a heavy object.

Ask: Can you jump as high?

Explain that the more the mass means the stronger the pull of gravity.

Use the string and ball taped together to perform the next demonstration.

Show the ball and state that it represents a planet and the string represent gravity.

Have a students place his finger in the loop, keeping the ball near his finger.

Have another student gently roll the ball away from the first person's finger.

Ask: How does the ball roll first?

What happens when the ball reaches the end of the string? (it begins to travel in a circular path.)

Have students visit NASA Kids- Weight  to determine how much they would weigh on different planets.

Evaluation:

The students will write down how much they would weigh in each planet.

The students will answer questions based on the results of their weight on each planet.

Why do you weigh more on Jupiter than on Pluto? (Jupiter has more mass than Pluto, therefore the gravity is greater and you weigh more).

Extension: Start a Space Club

• Have students brainstorm the name of their space club
• To help create a special name, students can type word, highlight it, then go to the Tools bar and click on the Thesaurus. Students can replace words to add interest
• Students can then create a logo for their club
• They can use draw/paint application to make one, use various clip art, or use a program like Kid Pix to stamp one, draw one or use its clip art
• Students then use word processing to write the club's mission statement
• Enter text and border or background
• Save and print

Homework:

  Have students find out how much each of their parents weigh and bring it to school to figure out how much his/her parents would weigh on different planets.

 

Fieldtrip:

Students can go on a virtual field trip through the Solar System by clicking here Virtual Tour.