Final answer:
PhET simulations in physics allow students to change parameters such as object size, simulation speed, and gravity strength to explore the effects on gravitational forces and orbital paths.
Step-by-step explanation:
The PhET simulations, such as the Gravity Force Lab and Gravity and Orbits, provide interactive environments for students to explore physics concepts. The simulations allow changes to object size, simulation speed, and gravity strength among other variables. By manipulating these parameters, students can observe the effects on gravitational forces, orbital paths, and other dynamics related to celestial bodies. For example, you can adjust the mass of objects to see how it alters the gravitational force in the Gravity Force Lab or change the distance between objects such as the Sun, Earth, Moon, and a space station in the Gravity and Orbits simulation to observe their orbital behavior and gravitational interactions.