A motionless place or object used for comparison is called a datum. It could also be called a reference point.
"reference"
reflected
to place an object in a fluid is... boring
why object stay in place
In theory, you can never truly detect if an object is in motion. Although I may travel in my car on the highway, I am not wrong to say that instead of myself moving across the earth, the earth is moving under me! Relativity proves to us that it is impossible to accurately show if an object is in motion or not. From a mathematical perspective, an object that you assume to be moving must be set relative to another object. This is in order to make accurate calculations about the object in question.
"reference"
wow...8th grade science online test question?
A landmark - or reference point.
reference point
That would be a reference point.
A reference point
A map
reflected
It depends on the object and the situation. Origin and source are two possible answers.
It means; Not moving, Unable to move, or be moved, Fixed in place, Motionless.
Inertia
[object Object]