The accumulation of capital refers to the process of "making money", or growing an initial sum of money through investment in production. Capitalism is based around the accumulation of capital, whereby financial capital is invested in order to realize a profit and then reinvested into further production in a continuous process of accumulation. In Marxian economic theory, this dynamic is called the law of value.
In a capitalist economic system capital assets can be owned and controlled by private persons, labor is purchased for money wages, capital gains accrue to private owners, and the price mechanism is utilized to allocate capital goods between competing uses.
In this case, we normally don't treat mobile phone as a capital.
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