48 meters.
12 m/s and 4 seconds, so 4*12=48.
The answer to your question is Speed
Answer:
The coefficient is 0.90
Explanation:
Drawing a diagram makes thing easier, we will assume that the acceleration tends to zero because it start barely moving.
The given question is incomplete. The complete question is as follows.
In a nuclear physics experiment, a proton (mass 
kg, charge +e = 
C) is fired directly at a target nucleus of unknown charge. (You can treat both objects as point charges, and assume that the nucleus remains at rest.) When it is far from its target, the proton has speed 
m/s. The proton comes momentarily to rest at a distance 
m from the center of the target nucleus, then flies back in the direction from which it came. What is the electric potential energy of the proton and nucleus when they are 
m apart?
Explanation:
The given data is as follows.
Mass of proton = 
kg
Charge of proton = 
Speed of proton = 
Distance traveled = 
We will calculate the electric potential energy of the proton and the nucleus by conservation of energy as follows.
= 
where, 
U = 
Putting the given values into the above formula as follows.
U =
= 
= 
Therefore, we can conclude that the electric potential energy of the proton and nucleus is .
Easy !
Take any musical instrument with strings ... a violin, a guitar, etc.
The length of the vibrating part of the strings doesn't change ...
it's the distance from the 'bridge' to the 'nut'.
Pluck any string. Then, slightly twist the tuning peg for that string,
and pluck the string again.
Twisting the peg only changed the string's tension; the length
couldn't change.
-- If you twisted the peg in the direction that made the string slightly
tighter, then your second pluck had a higher pitch than your first one.
-- If you twisted the peg in the direction that made the string slightly
looser, then your second pluck had a lower pitch than the first one.
