MY PBL PROJECT

If an object is heavier than the other shouldn't it fall before the lighter object?

Introduction:

Galileo predicted that heavy objects and light ones would fall at the same rate. This rule holds true only if gravity is the only force acting on the two objects. If the objects fall in air, then air resistance must also be taken into account. Larger objects experience more air resistance. Also, the faster an object is falling, the more air resistance it feels.

Materials:

  • A clear, plastic, rigid-walled tube

  • A solid rubber stopper

  • A clamp

  • A coin and a cotton ball

  • An air vacuum and oil

Procedures:

  • First, fuel the vacuum with the oil to start it.

  • Then, insert both the coin and cotton ball into the tube.

  • After doing so, you'll secure the rubber stopper into the tube.

  • Then you will flip the tube, seeing that the coin falls dramatically faster than the cotton ball.

  • After observing that, you'll then connect the vacuum into the clamp and suction out all the air. Leaving it without any air resistance.

  • Detach the tube from the vacuum and secure the clamp shut.

  • Flip it over once again and you'll see that both objects fall with the same speed due to the only acting force-- gravity.

Scientific Principle

Without air resistance everything will fall at the same speed, regardless of how much they weigh.

Air resistance- refers to a force that acts against relative motion of an object through a liquid or gas. It is also known as drag and acts in an opposite direction to the oncoming velocity.

Gravitational Pull- the force of attraction between all masses in the universe; especially the attraction of the earth's mass for bodies near its surface.

Safety Regulations:

  • Never operate electrical equipment while you are standing in or around water.

  • Never repair electrical cords or equipment unless qualified and authorized.

  • Always use caution when working near electricity.