To determine the output rating in watts for a pump lifting 8 kg of water per minute to a height of 3.50 m, the work done must be calculated using the formula for work, which is force times distance. The force is derived from the weight of the water, calculated as mass times gravitational acceleration. The total work done in one minute can then be converted into watts, knowing that 1 watt equals 1 joule per second. The discussion highlights the confusion among participants regarding the initial steps and components needed for the calculation. Understanding the relationship between watts, joules, and the work done is crucial for solving the problem effectively.