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combination of cell in series​

The combination of cells in which the negative terminal of a first cell is connected with the positive terminal of second cell and the negative terminal of a second cell is connected to the positive terminal of a third cell and so on is known as series combination of cells.

Explanation:

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Battery.

in simple terms, the principle states that the buoyancy force on an object is equal to the weight of the fluid displaced by the object, or the density of the fluid multiplied by the submerged volume times the gravitational acceleration, g. this is also known as upthrust.