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प्रश्न
A physical change is temporary. Explain.
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उत्तर
A physical change is defined as a change in which no new substance is formed.
A physical change is temporary because this change can be easily reversed by reversing the conditions. For example when ice is melted, it gets converted into water by absorbing heat. Water so formed can be easily converted to ice by cooling thus heat is released. Thus physical change is temporary.
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