Your friend says that inertia is a force that keeps things in their place, either at rest or moving at a constant speed. do you agree?

No

Explanation:

The error in the sentence is that inertia is not a force.

In fact, inertia is just the tendency of an object to keep its state of rest/motion if the net force acting on it is zero. As stated in Newton's First Law, also called Law of Inertia:

"An object at rest will remain at rest and an object in motion will continue its motion with constant velocity if the net force acting on it is zero"

This law basically tells us that as long as there are no forces acting on an object, the object mantains its state of rest/motion. On the contrary, in order to change the state of motion of an object, we need a net force different from zero.

bacteria that live on the ocean floor are sustained by phytoplankton. phytoplankton, microscopic marine photosynthetic organisms, have a vastly significant role to play not only in the marine food web of which they’re part of, but also on a more global scale. despite their infinitely small size in comparison to other marine organisms, these tiny creatures occupy an immensely important ecological niche: they are the foundation of the marine food web, and as primary producers, play key roles in supporting all other organisms in the marine environment, as well as in the regulation of the earth’s climate through the sequestration of carbon, oxygen production, and other related processes. phytoplankton account for roughly half of all global primary productivity; therefore, their significance extends far beyond the marine environment alone. there is an intriguing sense of irony in the realization that these tiny living beings that often live out their existence unnoticed and undetected by the rest of the world, have such a far-reaching impact on the lives of virtually all other living organisms on the planet, particularly on those in the marine environment. the world that we have become accustomed to has been and is continuously shaped by the workings of these miniscule yet vital “plants of the sea”.

hope this !

prndulum needs thread, weight clock to time swings