  We discuss solutions of the minimum energy problem in one dimensional
wireless sensor networks for the data transmission cost function $E(x_i,x_j) =
d(x_i,x_j)^a + \lambda \;d(x_i,x_j)^b$ with any exponent $a,b\in R$ and
$\lambda \geq 0$, where $d(x_i,x_j)$ is a distance between transmitter and
receiver. We define the minimum energy problem in terms of sensors signal
power, transmission time and capacities of a transmission channels. We prove,
that for the point-to-point data transmission method utilized by the sensors in
the physical layer, when the transmitter adjust the power of its radio signal
to the distance to the receiver, the solutions of the minimum energy problem
written in terms of data transmission cost function and in terms of the sensors
signal power coincide.
