A) The kinetic energy of an object is given by:

where m is the mass of the object, and v its speed. For the lion in our problem, m=45 kg and v=14.2 m/s, so its kinetic energy is

b) the increase in gravitational potential energy of the lion is given by:

where g is the gravitational acceleration, and

is the increase in altitude of the lion. In this problem,

, so the increase in gravitational potential energy is

c) When the fox reaches the top of the tree, its gravitational potential energy is

As it jumps, its kinetic energy is

So the total mechanical energy of the fox as it jumps is
Answer:
Explanation:
Two charged particles will vary in energy as we alter the distance between them.
To solve this problem it is necessary to apply the concepts related to the capacitance in the disks, the difference of the potential and the load in the disc.
The capacitance can be expressed in terms of the Area, the permeability constant and the diameter:

Where,
= Permeability constant
A = Cross-sectional Area
d = Diameter
Potential difference between the two disks,
V = Ed
Where,
E = Electric field
d = diameter
Q = Charge on the disk equal to 
Through the value found and the expression given for capacitance and potential, we can define the electric charge as





Re-arranging the equation to find the diameter of the disks, the equation will be:

Replacing,


Therefore the diameter of the disks is 0.03m