As the distance between two objects decreases, what happens to the force of gravity between the two objects

it remains the same
it increases
it decreases

itincreases or decreases, depending on the object

Waves are used in many practical applications to support work, entertainment, and health. one example is the use of ultrasound imaging to safely track the development of a growing fetus. what is a specific example of a practical application of waves in medicine, entertainment, safety, or other fields? provide a brief explanation of how the properties of waves are useful to that application.

The particles that are found in the nucleus of an atom are

How many excess electrons must be present on each sphere if the magnitude of the force of repulsion between them is 4.57×10−21 newtons?