The ball can't reach the speed of 20 m/s in two seconds, unless you THROW it down from the window with a little bit of initial speed. If you just drop it, then the highest speed it can have after two seconds is 19.6 m/s .
If an object starts from rest and its speed after 2 seconds is 20 m/s, then its acceleration is 20/2 = 10 m/s^2 .
(Gravity on Earth is only 9.8 m/s^2.)
The kelvin temperature/scale i think
Answer:
Fatigue is usually defined as the reversible decline of performance during activity, and most recovery occurs within the first hour. However, there is also a slowly reversible component that can take several days to reverse (155). Muscle injury also causes a decline in performance that reverses only very slowly.
Answer: D. 0.57
Explanation:
The formula to calculate the eccentricity 
of an ellipse is (assuming the moon's orbit in the shape of an ellipse):
Where:
is the apoapsis (the longest distance between the moon and its planet)
is the periapsis (the shortest distance between the moon and its planet)
Then:
This is the moon's orbital eccentricity
Answer:
magnetic trains works at the principle of repel on of the advantage is that they are fast and dont really need diesel
