London: E-books get heavier whenever users download a new text, a new study has suggested.
However the increase in weight does not make a significant difference, as each new book is just as heavy as a single molecule of DNA.
Thus, filling a 4GB Kindle to its storage limit would increase its weight by a billionth of a billionth of a gram.
Prof John Kubiatowicz a computer scientist at the University of California, Berkeley, explained in the New York Times that storing new data involves holding electrons in a fixed place in the device’s memory, the Telegraph reported.
Although the electrons are already present but keeping them still rather than allowing them to float around takes up extra energy – about a billionth of a microjoule per bit of data.
According to the scientists, E-readers can also become slightly heavier in summers, because they take up more energy from their exposure to sunlight.