Before the impact, let the velocity of the baseball was v m/s.
After being hit by the bat its velocity is -2v
So, change in velocity, Deltav=v-(-2v)=3v
Acceleration is defined as the rate of change in velocity, i.e. actual change in velocity divided by the time taken to change it. Time taken to change velocity is the time of actual contact of the bat and ball, i.e. 0.31 s.
a=(Deltav)/(Deltat)
=(3v)/0.37
Therefore, a/v=3/0.31=9.7 s^-1
So, the ratio of acceleration of the baseball to its original velocity is 9.7.
Answer: Only neurons will appear in the nervous system
Answer:
The answer of this is question is A.
By definition, the speed of an object is given by:

Where,
dr/dt: derived from the position with respect to time
Therefore, speed has units of length over units of time.
Thus, speed is a derived quantity, since it depends on the value of two other quantities.
Answer:
a derived quantity is:
C. Speed