This is a very interesting question. Here is what I think would happen if you dropped an anti-matter apple in a vacuum chamber made of titanium. First, let's assume that the anti-matter apple has the same mass and size as a regular apple, which is about 0.1 kg and 10 cm in diameter. Let's also assume that the anti-matter apple is made of anti-carbon, anti-oxygen, and anti-hydrogen atoms, which are the main constituents of organic matter. When you drop the anti-matter apple from a height of 1 m, it will accelerate downwards due to gravity. The acceleration of gravity on Earth is about 9.8 m/s^2, so the anti-matter apple will reach a speed of about 4.4 m/s when it hits the bottom of the chamber. At the moment of impact, the anti-matter apple will come into contact with the titanium atoms of the chamber. This will cause a violent annihilation reaction, where matter and anti-matter particles will convert into pure energy in the form of gamma rays and other subatomic particles. The amount of energy released by this reaction can be calculated using Einstein's famous equation E = mc^2, where E is energy, m is mass, and c is the speed of light.
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