Gravity and Balance

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Gravity and Balance

• Newtons Toy Box
• Activity 2

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Vocabulary

• Gravity
• Gravity support force
• Newton (N)
• Pound (lb)
• Weight

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What forces are acting on you right now?

• Gravity (pulling us downward to Earth)
• Magnetism (Earths magnetic field)

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Are you actually falling at this moment because
of gravity force?

• No, there is a force that opposes gravity.
• This force is called the gravity support force.
  This is an upward force.
• Gravity support force is equal in strength to
  gravitys downward pull. These forces are
  balanced.

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What is the source of gravity support force
(sitting in your chair)?

• The chair and/or the floor

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Is the force of gravity on you equal to the
support force of the chair on you? How do you
know?

• Each of us is not moving so, the two forces
  acting on each of us are balanced.

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What happens if a chair leg is weak and the chair
cannot produce a support force equal to your
weight? Why?

• The chair would break, and we would fall to the
  ground. The two forces, gravity and the gravity
  support force, would be unbalanced.

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Activity Sheet 2

• We will be using a spring scale, wooden ball, and
  a bag.
• We will be working in groups of 4.
• Read the activity sheet and begin the activity.
• Remember to read the scale on the Newton side
  instead of grams.

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Newton (N) Pound (lb)

• Newton is a metric unit of weight.
• Pound is a standard or customary unit of weight
  in the English system.

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Weight

• Weight is the strength of the gravity force
  pulling down on an object.

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Exit Slip or Homework

• Architects and engineers must keep gravity in
  mind when they design building. For example, the
  gravity support force of the walls must be strong
  enough to hold up the roof.
• Find examples in your neighborhoods where the
  gravity support force was not strong enough
  (hint any object that has collapsed)

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