Physics, chemistry, biology basics.
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Metal structures expand in hot weather.
Gaps prevent buckling and structural damage.
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Light from the submerged part changes direction when leaving water.
The brain traces rays backward and sees an apparent displacement.
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Their bodies tend to continue moving forward when the bus stops.
This is an example of inertia of motion.
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Chemical reactions inside a battery create an electric potential.
The stored chemical energy is converted into electrical energy.
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Melting occurs when a solid gains enough energy to become liquid.
It happens at the melting point under fixed pressure.
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Spectacle lenses change the convergence of light entering the eye.
They help focus images correctly on the retina.
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Newton's third law describes paired interaction forces.
Each force is matched by an equal force in the opposite direction.
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Solar cells use the photovoltaic effect.
They convert light directly into electrical energy.
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Freezing removes energy from a liquid until it forms a solid.
For pure water at standard pressure, this occurs at 0°C.
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The iris changes the size of the pupil.
This regulates how much light enters the eye.
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The rocket pushes exhaust gases downward.
The gases exert an equal and opposite force on the rocket.
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A microphone detects sound vibrations.
It converts them into corresponding electrical signals.
