Physical principle whose equation explains the changes in this puzzle's theme entries

Question:

Answer:

NEWTONSSECONDLAW

Length:

Similar Crossword Questions:

They're hidden in this puzzle's theme entries
Quadrennial occasion celebrated by this puzzle's theme entries
What this puzzle's theme entries take, vowel-wise
Many people get one in the summer (and so do this puzzle's theme entries)
Like the four theme entries in this puzzle, as it were
Decorative physical changes, and a hint to this puzzle's theme
Nickname for the three-letter abbreviation hidden in this puzzle's theme entries
Office building problem that's a hint to this puzzle's theme entries (see their last three letters)
This puzzle's theme entries, e.g.
First of a pair of letters swapped six times in this puzzle's theme entries
What this puzzle's theme entries have
Gym gear hidden in this puzzle's theme entries
Like fish for fish & chips -- or this puzzle's four theme entries
Just making things up, or a synonym for a three-word phrase describing this puzzle's theme entries
Where to find the theme entries of this puzzle, briefly
What this puzzle's theme entries are
Tone-Loc and Marky Mark and the Funky Bunch, e.g. ... or how this puzzle's theme entries might be described?
Word that has two diametrically opposed meanings (like this puzzle's eight theme entries)
Second of a pair of letters swapped six times in this puzzle's theme entries
What each of this puzzle's theme entries contains
The three of this puzzle's theme entries
Challenged, or what the theme entries in this puzzle should be
What the three theme entries in this puzzle are, in either of two ways
What this puzzle's theme entries probably do?
Levels that are split in this puzzle's theme entries