1. The problem statement, all variables and given/known data A motor lifts a block of mass 0.050kg at a constant velocity of 0.40m s-1. The current in the motor ia 85mA and the potential difference across it is 3.0V. Calculate the efficiency of the motor 2. Relevant equations Ek = 1/2 x mv2 Electrical power = VIt 3. The attempt at a solution Ig to the electrical power as 0.255W, and kinetic energy of the block as 0.004J. But how do I get the power of the block, or the electrical energy of the motor?