Answer: -39.2 m/s or 39.2 m/s directed downwards
Explanation:
This situation is a good example of Free Fall, where the main condition is that the initial velocity must be zero
, and the acceleration is constant (acceleration due gravity).
So, in order to calculate the final velocity
of the rock just at the moment it hitsthe bottom of the cliff, we will use the following equation:

Where:
is the acceleration due gravity (directed downwards)
is the time it takes to the rock to fall down the cliff

This is the rock's final velocity and its negative sign indicates it is directed downwards
Answer:1
Explanation:
If
s=displacement
v=velocity of particle
a=acceleration of particle
acceleration can be written as rate of change of velocity
so 
multiply and divide by 




option 1 is correct
Acceleration can be any change in speed, increasing or decreasing.
You haven't said whether the ball is speeding up or slowing down.
If its acceleration is positive ... speed is increasing ... then in 2.5 seconds,
it GAINS (0.5 m/s² x 2.5 sec) = 2.5 m/s of speed. Added to its initial
speed of 2.0 m/s, it ends up moving at 4.5 m/s.
If its acceleration is negative ... speed is decreasing ... then in 2.5 seconds,
it LOSES (0.5 m/s² x 2.5 sec) = 2.5 m/s of speed. Added to its initial
speed of 2.0 m/s, it ends up moving at -0.5 m/s. That means that it ends up
moving in the opposite direction compared to its direction at the beginning of
the change.
Velocity of vw bug is given as
towards north
velocity of imphala is given as
towards south
now we need to find velocity of imphala relative to bug


so the speed is 101 mpH towards south so correct option is C
<span> </span>J. J. <span>Thomson discovered cathode rays</span>