Power of motor needed to carry 2kg of weight at speed of 10 kmph
The mass considered by itself can not be used to calculate the required power. You must consider friction, the slope of the surface that the vehicle must climb, the rate of acceleration that must be achieved and the aerodynamic drag. There are answers to questions here that cover this in more detail. You should see a list of related question on the right side if the screen when looking at this answer.

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