Answer:
The ratio of kinetic energies of 5 kg object to 20 kg object is 1:1.
Explanation:
Kinetic energy is defined as energy possessed by an object due to its motion.It is calculated by:

Kinetic energy of the 5 kg object.
Mass of object,m = 5 kg
Velocity of an object = v

Kinetic energy of the 20 kg object.
Mass of object,m' = 20 kg
Velocity of an object = v'

The ratio of the kinetic energy of the 5 kilogram object to the kinetic energy of the 20-kilogram object:

Given that, v = 2v'

The ratio of kinetic energies of 5 kg object to 20 kg object is 1:1.
<span>Notice for the Carbon question they were the same element and the shared the same number of protons. so i think d. is the answer</span>
Answer:
F = - k (x-xo) a graph of the weight or applied force against the elongation obtaining a line already proves Hooke's law.
Explanation:
The student wants to prove hooke's law which has the form
F = - k (x-xo)
To do this we hang the spring in a vertical position and mark the equilibrium position on a tape measure, to simplify the calculations we can make this point zero by placing our reference system in this position.
Now for a series of known masses let's get them one by one and measure the spring elongation, building a table of weight vs elongation,
we must be careful when hanging the weights so as not to create oscillations in the spring
we look for the mass of each weight
W = mg
m = W / g
and we write them in a new column, we make a graph of the weight or applied force against the elongation and it should give a straight line; the slope of this line is sought, which is the spring constant.
The fact of obtaining a line already proves Hooke's law.
(a) If the cornea were simply thin lens then power will be 43 diopters.
(b) This is a concave lens
The cornea is the transparent front part of the eye that covers the iris, pupil, and anterior chamber. Despite injury or disease, the cornea can still repair itself quickly. However, there are situations where damage is too severe for the cornea to heal on its own – such as with a deep injury to the cornea. The following symptoms may indicate that the cornea has sustained a substantial infection, injury or disease: Blurred vision Pain Redness.
Along with the anterior chamber and lens, the cornea refracts light, accounting for approximately two-thirds of the eye's total optical power. In humans, the refractive power of the cornea is approximately 43 diopters.
There are two types of lenses: converging and diverging and here if the cornea was simply thin then the diverging or concave lens is used in the eyes which is thin in the center than their edges.
To know more about cornea, refer: brainly.com/question/13866057
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