As per the question, the mass of meteorite [ m]= 50 kg
The velocity of the meteorite [v] = 1000 m/s
When the meteorite falls on the ground, it will give whole of its kinetic energy to earth.
We are asked to calculate the gain in kinetic energy of earth.
The kinetic energy of meteorite is calculated as -
![Kinetic\ energy\ [K.E]\ =\frac{1}{2} mv^2](https://tex.z-dn.net/?f=Kinetic%5C%20energy%5C%20%5BK.E%5D%5C%20%3D%5Cfrac%7B1%7D%7B2%7D%20mv%5E2)
![=\frac{1}{2}50kg*[1000\ m/s]^2](https://tex.z-dn.net/?f=%3D%5Cfrac%7B1%7D%7B2%7D50kg%2A%5B1000%5C%20m%2Fs%5D%5E2)

Here, J stands for Joule which is the S.I unit of energy.
Explanation:
Large electrical shifting magnets have concentrated retaining strength to lift dense, ferric objects and a deep-reaching magnetization. An immensely useful materials management technique is these electromagnetic rises.
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
.
The object is at rest is the answer.