Select all that is true about the Earth's gravitational acceleration: \( \square \) Is about \( 5 \mathrm{~m} / \mathrm{s}^{2} \) \( \square \) Depends on the mass \( \square \) Always points downward \( \square \) Is about \( 10 \mathrm{~m} / \mathrm{s}^{2} \)

Gravity has intrigued humanity for centuries, and Isaac Newton is often credited with formulating the law of universal gravitation in the 17th century. His work laid the foundation for understanding how objects interact with one another due to their mass, leading to a deeper insight into celestial mechanics and the motion of planets and moons. In practical terms, gravitational acceleration is crucial for various applications, from designing roller coasters to ensuring satellites maintain their orbits. For instance, engineers must account for gravitational forces when constructing buildings to withstand potential earthquakes, and space agencies design spacecraft trajectories based on gravitational pull to optimize fuel efficiency during launches and landings.