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प्रश्न
An ice cube is suspended in vacuum in a gravity free hall. As the ice melts it
विकल्प
will retain its cubical shape
will change its shape to spherical
will fall down on the floor of the hall
will fly up.
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उत्तर
As the ice cube melts completely, the water thus formed will have minimum surface area due to its surface tension. Any state of matter that has a minimum surface area to its volume takes the shape of a sphere. Therefore, as the ice melts, it will take the shape of a sphere.
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