What is the main difference between a conceptual model and a physical model?
A physical model is a physical structure that depicts the physical attributes of the modeled system, such as size, volume, and weight. The conceptual model portrays a system to aid individuals in predicting how the system would perform as it imitates a subject that the model represents. It is also a collection of ideas.
A 4.80-kg watermelon is dropped from rest from the roof of an 18.0-m-tall building and feels no appreciable air resistance. (a) Calculate the work done by gravity on the watermelon during its displacement from the roof to the ground. (b) Just before it strikes the ground, what is the watermelon’s (i) kinetic energy and (ii) speed? (c) Which of the answers in parts (a) and (b) would be different if there were appreciable air resistance?