What Is Free Fall? | Physics in Motion

Summary

In 'Physics in Motion,' Adrian Monte explores the concept of freefall, explaining that it occurs when an object is only under the influence of gravity. He recounts Galileo's groundbreaking discovery in the 16th century that all objects fall at the same acceleration, regardless of their mass. Demonstrations, including dropping a watermelon and a cantaloupe, illustrate this principle. Monte also examines a freefall problem involving a ball thrown upwards, calculating its maximum height using kinematic equations. Ultimately, the segment emphasizes the fundamental role of gravity in understanding motion, inviting viewers to further engage with the topic through available resources.

Takeaways

• 😀 Freefall is defined as the motion of an object influenced only by gravity.
• 😀 Historical beliefs held that heavier objects fell faster, a notion disproven by Galileo.
• 😀 Galileo's experiments showed that all objects fall at the same rate of acceleration, regardless of mass.
• 😀 The acceleration due to gravity on Earth is approximately 9.8 meters per second squared.
• 😀 A demonstration with a watermelon and a cantaloupe illustrates that they hit the ground simultaneously.
• 😀 On the moon, the feather and hammer dropped at the same rate due to gravity's influence.
• 😀 An object in freefall can still be in motion upwards or momentarily at rest at its peak height.
• 😀 A ball thrown upwards at 10 meters per second will decelerate at -9.8 meters per second squared until it reaches maximum height.
• 😀 Using kinematic equations, the maximum height of the ball can be calculated to be 5.1 meters.
• 😀 The speed of the ball upon returning to the thrower's hand will be the same (10 meters per second) but in the opposite direction.

Q & A

What is free fall?

Free fall is when an object is influenced only by gravity, without any other forces acting on it.

Who was Galileo, and what did he discover about free fall?

Galileo was a 16th-century scientist who proposed that all objects, regardless of their mass, fall at the same rate of acceleration when in free fall.

How does the mass of an object affect its free fall?

In free fall, the mass of an object does not affect the rate at which it falls; all objects fall at approximately 9.8 meters per second squared near Earth's surface.

What experiment did Adrian Monte conduct to illustrate free fall?

Adrian Monte dropped a watermelon and a cantaloupe from the same height to demonstrate that both hit the ground simultaneously, verifying Galileo's theory.

What is the acceleration due to gravity on Earth?

The acceleration due to gravity near the Earth's surface is approximately 9.8 meters per second squared.

How does air resistance affect free fall?

Air resistance is not considered in this segment since the focus is solely on the effects of gravity in free fall.

What happens to a ball thrown upwards in free fall?

When a ball is thrown upwards, it initially moves against gravity, slows down, and eventually stops momentarily at its maximum height before falling back down.

What equation can be used to find the maximum height of a ball thrown upwards?

The equation used is: final velocity squared equals initial velocity squared plus two times acceleration times displacement.

What was the maximum height reached by the ball in the example?

The ball reached a maximum height of 5.1 meters before it started to fall back down.

What will be the velocity of the ball when it returns to the thrower's hand?

The ball will return at a velocity of negative 10 meters per second, which is the same speed it left the thrower's hand, but in the opposite direction.