Physics · Grades 9–12
Free fall from rest
Treat g as constant, ignore air resistance, and start from rest.
Rule and assumptions
Treat g as constant, ignore air resistance, and start from rest.
d = ½gt²
Worked examples
An object falls from rest for 1 s in an ideal model with g = 2 m/s² and no air resistance. Find the downward distance. Round to 3 decimal places if needed. Answer in m.
d = ½gt² 0.5 × 2 × 1² = 1
1 m
An object falls from rest for 12 s in an ideal model with g = 5 m/s² and no air resistance. Find the downward distance. Round to 3 decimal places if needed. Answer in m.
d = ½gt² 0.5 × 5 × 12² = 360
360 m
Try two questions
An object falls from rest for 7 s in an ideal model with g = 8 m/s² and no air resistance. Find the downward distance. Round to 3 decimal places if needed. Answer in m.
An object falls from rest for 2 s in an ideal model with g = 2 m/s² and no air resistance. Find the downward distance. Round to 3 decimal places if needed. Answer in m.
Answers and reasoning
Answers and marking notes
- 196 m
d = ½gt² 0.5 × 8 × 7² = 196
- 4 m
d = ½gt² 0.5 × 2 × 2² = 4
Further reading and review references
These are reference links, not copied exercises, institutional endorsement or proof of independent review.
Learning preview · independent educational and translation review required. Suggested grades are not official curriculum alignment.