Question

An object is dropped from rest from the top of a 400 m cliff on Earth. How long does it take to hit the ground?

Answer 1

So this is dealing with Kinematic Equations. And you are also dealing with a free falling body. So, you will need this equation: \[t=\sqrt{\frac{ 2 \times D }{ g }}\]
D stands for the distance, G stands for gravity and t stands for time. But if you have a technical teacher be sure to use (a) for gravity. So you know the distance is 400. Do you know what g is?

Answer 2

u can take g equal to 10 and the answer would be 4root5 seconds but remember and be cautious of the units used gravity is always in m/sec^2 so always convert distance into meters.
fan and medal

Answer 3

Again, if your teacher is precise you might want to use 9.81m/s for a or gravity