More Dominoes, Same Energy: The Conservation Mystery

The conservation of energy is a fundamental principle in physics, and the concept of dominos falling sequentially without breaking this law can be explained by understanding the interplay of potential and kinetic energy. When a domino is set upright, it gains potential energy, which is then converted into kinetic energy as it falls. This kinetic energy is transferred to the next domino, which, in turn, falls and releases its own potential energy. This chain reaction continues, with each falling domino contributing its potential energy, ensuring that the energy in the system remains conserved. The energy added to the system when setting up the dominos is crucial, as it provides the necessary potential energy for the chain reaction to occur.

Potential energy is stored in dominos when they are stood up

When dominos are stood up, they store potential energy. This energy is added to the system when the dominos are placed in an upright position. The potential energy is converted into kinetic energy when a domino falls, which is then transferred to the next domino, knocking it over. This process repeats for each domino in the sequence.

Each domino has gravitational potential energy, which is proportional to the height of the centre of mass from a reference point. When a domino is standing, its centre of mass is higher than when it is lying flat. Therefore, when a domino falls, it moves towards a state of lower potential energy.

The energy required to tip a domino past the point where it will fall naturally is less than the total energy released by the domino falling over. This is because the falling domino releases energy in the form of sound, heat, and mechanical vibration. This energy is then transferred to the next domino in the sequence, which only needs enough energy to overcome its threshold energy and fall over.

The initial energy input required to start the domino effect comes from the person who sets up the dominos. They must do work against gravity to place each domino in an upright position, thus adding potential energy to the system. This energy is then released when the dominos fall, demonstrating the conservation of energy.

In summary, the potential energy stored in dominos when they are stood up is converted into kinetic energy as they fall. This energy is then transferred to the next domino, allowing the sequence to continue. The energy added to the system when the dominos are set up is greater than the energy required to knock them down, ensuring the conservation of energy.

The energy used to knock down the dominos comes from the dominos themselves

When dominos are set up, they are in a state of unstable equilibrium, also known as a metastable state. This means that they are in a state where they have not achieved the minimum possible energy state yet. The energy in this case is gravitational potential energy, which is directly proportional to the height of the centre of mass from a reference point.

When a domino is standing up, it has more energy than when it is lying flat. Therefore, when you knock over the first domino, it tends to fall down and achieve a state of lower potential energy. This is because the energy you supplied to the domino by knocking it over is added to the domino's own potential energy. This is where the energy to knock over the next domino comes from.

Each domino has potential energy (from being put upright) that is used (converted to kinetic energy) when it falls. This energy is then transferred to the next domino, knocking it over. This continues down the line. The kinetic energy of the falling domino is more than enough to push over the next, even if it is larger. The larger domino has even more potential energy locked inside it, which is then converted into kinetic energy and used to push the next one, and so on.

Each domino slows down a bit on its way to the ground due to the next domino in its way. So, it doesn't hit the ground as hard as it would if there wasn't another domino in the way. This available energy is then used to push over the next domino.

The energy is converted from potential to kinetic energy

When a domino is standing, it has potential energy. This energy is converted into kinetic energy when the domino falls. The energy is initially supplied when the dominos are set up. Each domino has its own potential energy, which is released as it falls, and this energy is then transferred to the next domino.

Each domino is slowed down slightly as it falls by the domino in its way. This means that it does not hit the ground as hard as it would have done if there was no other domino in the way. This reduction in speed results in a reduction in kinetic energy, and this, in turn, reduces the energy available to push over the next domino. However, the energy supplied when the dominos were set up is enough to keep the cascade going.

The energy from the falling dominos is also lost to sound, heat, and mechanical vibration, which results in a constant speed for the cascade.

To summarise, the energy is converted from potential to kinetic energy as each domino falls.

Energy is lost through sound, heat and mechanical vibration

The law of conservation of energy states that energy cannot be created or destroyed, only transferred or converted between forms. When a row of dominos is set up, energy is stored within the system in the form of gravitational potential energy. This energy is then released as kinetic energy when the dominos start falling. However, the efficiency of energy transfer decreases over time due to losses through sound, heat, and mechanical vibration.

Each domino in the row has its own gravitational potential energy, which is converted into kinetic energy as it falls. The kinetic energy of the falling domino is then transferred to the next domino in the row, knocking it over. This process repeats for each domino in the row. However, with each transfer of energy, some amount of energy is lost to sound, heat, and mechanical vibration. These losses accumulate over time, resulting in a decrease in the efficiency of energy transfer.

Initially, the kinetic energy of the falling dominos is greater than the threshold energy required to knock over the next domino. However, as energy losses accumulate, there may come a point where the kinetic energy of the falling domino is no longer sufficient to knock over the next one, bringing the cascade to a halt.

The energy losses due to sound, heat, and mechanical vibration play a crucial role in determining the sustainability of the domino cascade. While the gravitational potential energy of each domino provides additional energy to the system, the cumulative effect of energy losses can eventually outweigh the gains, leading to a net loss of energy in the system and bringing the cascade to an eventual stop.

In summary, while the law of conservation of energy is not violated in the domino cascade, the energy losses through sound, heat, and mechanical vibration influence the sustainability of the cascade. These losses highlight the importance of considering all forms of energy transfer and conversion in a system to fully understand its dynamics and predict its long-term behavior.

The energy transfer efficiency decreases over time

The energy in the next falling domino doesn't just come from the energy transferred from the domino that hits it. If that were the case, then the cascade would eventually stop. But each standing domino also contains its own potential energy, which was given to it by its being lifted into an unstable equilibrium by whoever set them up.

Each domino falling releases potential energy, which is converted into kinetic energy, thus fuelling the cascade. However, sound waves and heat, as well as mechanical vibration of the individual dominos, will increase, thus decreasing the efficiency of energy transfer from each collision.

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