Answer:
The options are not shown, so let's derive the relationship.
For an object that is at a height H above the ground, and is not moving, the potential energy will be:
U = m*g*H
where m is the mass of the object, and g is the gravitational acceleration.
Now, the kinetic energy of an object can be written as:
K = (1/2)*m*v^2
where v is the velocity.
Now, when we drop the object, the potential energy begins to transform into kinetic energy, and by the conservation of the energy, by the moment that H is equal to zero (So the potential energy is zero) all the initial potential energy must now be converted into kinetic energy.
Uinitial = Kfinal.
m*g*H = (1/2)*m*v^2
v^2 = 2*g*H
v = √(2*g*H)
So we expressed the final velocity (the velocity at which the object impacts the ground) in terms of the height, H.
Human error (average human reaction time is .2 seconds)
Answer:
1 second later the vehicle's velocity will be:

5 seconds later the vehicle's velocity will be:

Explanation:
Recall the formula for the velocity of an object under constant accelerated motion (with acceleration "
"):

Therefore, in this case
and 
so we can estimate the velocity of the vehicle at different times just by replacing the requested "t" in the expression:

When you look at this, you might not be sure which way to divide ...
Should you divide 6 by 5 or 5 by 6 ?
Here's a case where you can use your units to decide.
The question wants to know the 'period'. That's a length of time,
so the answer needs to have units of time.
If you divide 'cycles' be 'time', you'll get 'cycles/second'.
That's Hz. It's frequency, not time.
If you divide 'time' by 'cycles', you'll get 'seconds/cycle'.
That's time, and it's exactly the definition of 'period'.
Period = (6 seconds) / (5 cycles)
= (6 / 5) seconds/cycle
= 1.2 seconds
Hi
I think the answer is:
GRAVITATIONAL POTENTIAL ENERGY TRANSFORMS INTO KINETIC ENERGY.
HOPE IT HELPS.