Acceleration is defined as the change in velocity divided by

Time elapsed

Explanation:

Acceleration is a vector quantity. It is defined as:

where

v is the final velocity

u is the initial velocity

t is the time elapsed

Acceleration is measured in meters per second squared (m/s^2). It must be noticed that acceleration is a vector, so it also has a direction. In particular:

- when acceleration is negative, it means that the object is slowing down, so acceleration is in opposite direction to the velocity

- when acceleration is positive, it means that the object is speeding up, so acceleration is in the same direction as the velocity

kepler used the data from tycho blahe (his mentor) to construct the laws of planetary motion.

see the picture for the vector

the magnitude of the vector by pythagorean theorem

r = √( (-10)^2 + (3)^2 ) = √109

magnitude = √109 units

the direction angle between vector and x-axis is

tan^(-1)(3/10) = 16.699

so the direction is approximately 16.7 degrees north of west