Energy conversions in a game of billiards

AI Thread Summary
The discussion centers on the energy conversion involved in a billiards game, specifically how the kinetic energy of the cue ball is generated. Participants explore the initial energy sources, concluding that the energy originates from the body's chemical energy, which is transformed into mechanical energy for muscle movement. The cue stick's movement is debated, with some suggesting gravitational potential energy, although it is clarified that the cue can move horizontally without it. The conversion process involves chemical energy creating an electrical gradient in muscle cells, leading to muscle contraction. Overall, the conversation highlights the intricate relationship between body energy and the mechanics of billiards.
Kaushik
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Summary: When we hit the cue ball which energy is being converted into the kinetic energy of the ball?

When we hit the cue ball which energy is being converted into the kinetic energy of the ball?
 
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This sounds like a homework question. What do you think?

What has energy before you hit the ball?
 
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mfb said:
This sounds like a homework question.
I am just asking this out of curiosity
mfb said:
What has energy before you hit the ball?
Our body/arms and the balls potential energy?
 
The ball doesn't change its height, no relevant potential energy involved.

Initially the energy is somewhere in you, sure, but I was more thinking about the situation directly before you hit the ball - with the moving cue.
 
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mfb said:
The ball doesn't change its height, no relevant potential energy involved.

Initially the energy is somewhere in you, sure, but I was more thinking about the situation directly before you hit the ball - with the moving cue.
mfb said:
with the moving cue.
Does the cue have potential energy (Which then becomes kinetic energy)?
 
Kaushik said:
Does the cue have potential energy (Which then becomes kinetic energy)?
What form of potential energy are you suggesting? Elastic, gravitational, electric, spiritual ...?
What makes the cue move, in your experience?
 
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haruspex said:
What form of potential energy are you suggesting? Elastic, gravitational, electric, spiritual ...?
What makes the cue move, in your experience?
I was suggesting 'gravitation potential energy' as it is kept at some height from the Earth's surface.

After thinking about it, i feel like it does not make sense. Answer to the question 'Why do you think that it does not make sense?' is given below.

Let us consider a cue lying on the Earths surface. It has no gravitational potential energy but it is still possible to move it horizontally.

So is it the energy in our body which transforms into kinetic energy of the cue, later into kinetic energy of the ball?
 
Kaushik said:
So is it the energy in our body which transforms into kinetic energy of the cue, later into kinetic energy of the ball?
Yes.
Any thoughts on the transformations within the body?
 
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haruspex said:
Any thoughts on the transformations within the body?
After surfing on the internet for a while, I learned that it is the chemical energy in our body (stored in the mitochondria due to the food we eat) which transforms into mechanical energy of the muscles.
Is the above correct?
If yes, how exactly does the chemical energy get converted into mechanical energy of the muscles?
 
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Kaushik said:
After surfing on the internet for a while, I learned that it is the chemical energy in our body (stored in the mitochondria due to the food we eat) which transforms into mechanical energy of the muscles.
Is the above correct?
If yes, how exactly does the chemical energy get converted into mechanical energy of the muscles?
Yes, that explanation skips a step.
The chemical energy is used to move ions around, creating an electrical gradient. This causes fibres in each muscle cell to slide past each other. See e.g. https://opentextbc.ca/biology/chapter/19-4-muscle-contraction-and-locomotion/
 
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