How do yo calculate how long would take for an object to fall?

[XinXan]

Say a ball of 1Kg, you let it fall (frefall) from 50 meters, how long does it take to reach the ground? Whats the formula

[rapsaodan84]

Say a ball of 1Kg, you let it fall (frefall) from 50 meters, how long does it take to reach the ground? Whats the formula

If you ignore the resistance of the air then the formula you're looking for is:
distance = initial velocity (0 if the object is dropped) • time + ½ • gravity • time^2
from there you can calculate time.

Check "Example Problem A" here: http://www.physicsclassroom.com/class/1DKin/Lesson-6/Kinematic-Equations-and-Free-Fall

[Gleb Gamow]

Say a ball of 1Kg, you let it fall (frefall) from 50 meters, how long does it take to reach the ground? Whats the formula

If you ignore the resistance of the air then the formula you're looking for is:
distance = initial velocity (0 if the object is dropped) • time + ½ • gravity • time^2
from there you can calculate time.

Check "Example Problem A" here: http://www.physicsclassroom.com/class/1DKin/Lesson-6/Kinematic-Equations-and-Free-Fall

Okay, so what's the formula in a Flat-earth model where gravity doesn't exist?