Every body continues in its state of rest, or of uniform motion in a right line, unless it is compelled to change that state by forces impressed upon it.
About this quote
- What does it mean?
- Newton states the law of inertia: a body remains at rest or moves uniformly unless acted upon by external forces.
- In plain terms
- Objects keep moving or stay still unless a force changes them.
- What can you take from it?
- Inertia governs motion without external influence.
Where it applies
Putting it to work
Questions to consider
- Why does inertia exist?
- How does inertia affect everyday technology?
Another view
Relativistic effects modify inertia at high speeds.
More from Isaac Newton
We are to admit no more causes of natural things than such as are both true and sufficient to explain their appearances.
Permalink to quote #21 The alternation of motion is ever proportional to the motive force impressed; and is made in the direction of the right line in which that force is impressed.
Permalink to quote #23 It is indeed a matter of great difficulty to discover, and effectually to distinguish, the true motions of particular bodies from the apparent; because the par…
Permalink to quote #20
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