# Spinning a bucket of water in a vertical circle - Inertia

• candypie90
In summary, the concept of inertia explains why the water in a bucket does not fall out when spinning in a vertical circle. Inertia is the resistance of any physical object to changes in its velocity. At the top of the circle, the water is moving in a certain direction and according to inertia, it will continue to move in that direction unless acted upon by an external force. Therefore, the water stays in the bucket due to its inertia and does not fall out. This can be understood by considering the bucket catching the water at the top of the circle and the concept of inertia explaining the water's continued motion.

#### candypie90

Homework Statement
How or why does inertia caused the water in a bucket not to fall out when spinning in a vertical circle.
Relevant Equations
Is the bucket catching the water?
Homework Statement: How or why does inertia caused the water in a bucket not to fall out when spinning in a vertical circle.
Homework Equations: Is the bucket catching the water?

I know Inertia is the resistance of any physical object to any change in its velocity.

Please show an attempt at a solution, if you are familiar with centripetal forces and centripetal accelerations.

candypie90 said:
Is the bucket catching the water?
I assume this is your attempt at an explanation. The problem is that it doesn't really answer the question. You were asked to use the concept of inertia to explain why the water doesn't fall out the bucket, but if there's a connection between the ideas of "bucket catching the water" and "resistance to changing velocity," it isn't obvious.

I know Inertia is the resistance of any physical object to any change in its velocity.
Consider the water and the bucket at the top of the vertical circle. Which way is the water moving? What does the concept of inertia tell you about where the water will be a moment later?

## What is inertia?

Inertia is the tendency of an object to resist changes in its state of motion. This means that an object at rest will stay at rest, and an object in motion will continue moving in the same direction and at the same speed, unless acted upon by an external force.

## How does inertia relate to spinning a bucket of water in a vertical circle?

When a bucket of water is spun in a vertical circle, the water inside the bucket wants to continue moving in a straight line due to its inertia. However, the bucket exerts an inward force on the water, causing it to change direction and move in a circular path.

## What is the role of gravity in spinning a bucket of water in a vertical circle?

Gravity is the force that pulls the water towards the center of the circle as it is being spun. This force is necessary to keep the water moving in a circular path and prevent it from flying out of the bucket.

## How does the speed of the bucket affect the water inside when spinning in a vertical circle?

The speed of the bucket affects the amount of centripetal force exerted on the water. If the speed is too slow, the water may not have enough force to move in a circular path and will instead fall to the bottom of the bucket. If the speed is too fast, the water may experience too much force and splash out of the bucket.

## What would happen to the water inside the bucket if there was no inertia?

If there was no inertia, the water would not resist changes in its state of motion and would move in a straight line tangential to the circle. This would cause the water to spill out of the bucket and not form a circular path.