Question

An electric clothes dryer operates on a voltage of 220 V and draws 20 A. How long does the dryer take to dry a full load of clothes? The clothes weigh 6.0 kg when wet and 3.7 kg when dry. Assume that 65% of the electric energy going into the dryer is used to evaporate water. The heat of evaporation for water is 539 kcal/kg

Answer 1

The length a load of clothes takes to dry depends on a number of factors such as the temperature of the ambient air and the humidity and how wet the clothes are when they are put in the dryer. How wet they are when put in the dryer. It would also be influenced by what the clothes are made of and not just how much they weigh. As an answer say it would take 52 minutes. That will be pretty close to the right answer. If asked how you arrived at the answer, say your took a wild guess. To be honest, I don't think the problem can be solved with any kind of meaningful answer arrived at with the information given. Also, if the teacher provides an answer it would probably not match the real world or could not be tested easily.