Could you cook a chicken by hitting it? While this meme does not sound like a good physics question at first glance, it is indeed a great question. Actually, I thought I had already answered. In 2010, I investigated the possibility of cooking a turkey by dropping it.
But this question is still a big physical issue, so let's get down to it.
cooking is heating
wants to cook a chicken You can grill it, roast, roast or even microwave. The point is that you need to raise the temperature of the chicken from about room temperature to 165 degrees Fahrenheit (74 degrees Celsius). Cooking chicken does two things. First, cooked meat is easier for humans to digest (and we get more calories from cooked than raw meat). Second, at 1
Although cooked chicken is not just hot raw meat, I suppose it is. Cooking makes chicken eggs more than just temperature changes, but let's gloss over them. The real question is: How much energy does it take to change the temperature of chickens? For this we can consider the change of the thermal energy. This energy depends not only on the temperature change, but also on the mass of the object and the type of object. As an equation, it looks like this.
In this expression ΔT is the temperature change and C is the specific heat capacity. What is the specific heat capacity? Perhaps an example helps: Suppose I heat up the same masses of steel and plastic foam. Steel and foam are at the same temperature but require much more energy to heat the steel because it has a specific heat capacity of 0.49 joules per gram per degree Celsius while the foam is only 0.3.
What about chicken? What is the specific heat capacity of a chicken? I do not know this value. If I had to guess, I would use the value for water at 4,186 J / gC (water has a very high specific heat capacity). Or I could use something similar to chicken. How about Turkey? Turkey is like chicken, right? By chance, I have already measured the specific heat capacity of turkey.
How to measure the specific heat capacity. Take some turkey (make sure you know the mass and the starting temperature). Now put it in hot water in an insulated box. After a while, measure the temperature of the water and the turkey. Since I know the heat capacity of water, I can use this decrease in water temperature to calculate the increase in turkey's thermal energy. Here is a graphical representation of the temperature (just to show you that it is real).
This results in a specific heat capacity of 6.018 J / g / C. Surprisingly, this is higher than water.
Conservation of Energy
If I assume that chicken is similar to turkey, I can calculate the change in heat energy to cook it. But where would this energy come from? Yes, it comes from a beating hand. How much energy is there in a handshake? Suppose you move your hand with a mass m h at a certain velocity v. In this case, it will have a kinetic energy of the following height:
When the hand hits the chicken, the hand will stand still. As there is no kinetic energy now, the energy had to go somewhere. It is probably mostly an increase in the thermal energy of the chicken – but also the hand! To cook a turkey, you also need to cook your hand. But let's not worry about the hand now, except to guess that half of that energy goes into the chicken and half into the hand.
How many slaps?
We have all the main ideas. Now all we have to do is to calculate. Let us make some assumptions:
- Crowd of chicken = 2 kilograms. Do not worry, if you do not like this estimate, you can change it below. Oh, and this is for a whole chicken that you would buy at the store.
- Starting temperature = 23 ° C, final temperature = 74 ° C.
- Hand mass = 200 grams (total estimate here).  Speed of a punching hand = 3 meters per second. Let's grow up at 5 meters per second.
- Energy factor = 0.5. This is the percentage of energy that is released to the chicken. I will use the symbol "f" for this.
Now I can calculate the change in chicken temperature for 1 shot.
OK, I know you disagree with my assumptions. Here's a Python calculation that lets you change and re-execute the values. Yes, you can actually change the values - you will not break anything.
That said, it would take 49,000 strikes to cook your chicken. That requires a very high impact speed. Now to some homework.
- Let's say you hit a chicken once a second. You want to eat chicken at 18:00. When should you start beating?
- What if you include thermal radiation? Use the Stefan-Boltzman equation to account for the energy lost during beating. Nobody ever said physics was easy (but it's fun).
- My estimate for a velocity was high – too high. Use video analytics or something else for better impact speed. Please do not beat people, that's not nice.
- How do you prevent your hand from being cooked? Be creative.
- Repeat my turkey experiment and measure the specific heat capacity of chickens.
- Find the mass of a human hand without bad stuff happening.
A final comment. I welcome all strange cook memes as they are essentially physics memes.
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