Answer:
Part a)

Part b)

Explanation:
As we know that the energy of capacitor when it is not connected to potential source is given as

As we know that initial energy is given as

now we know that capacitance of parallel plate capacitor is given as

now the new capacitance when distance is changed from 3.80 mm to 1.45 mm



Now the new energy of the capacitor is given as


Part b)
Now if the voltage difference between the plates of capacitor is given constant
now the energy energy of capacitor is


now when capacitance is changed to new value then new energy is given as



Complete Question
The complete question is shown on the first uploaded image
Answer:
A

B

C
The correct option is B
Explanation:
From the question we are told that
The refractive index of water is 
The refractive index of ethanol is 
Generally the threshold velocity for creating Cherenkov light from a charged particle as it travels through water is mathematically evaluated as

Where c is the speed of light with value 


Generally the threshold velocity for creating Cherenkov light from a charged particle as it travels through water is mathematically evaluated as

=> 
=> 
Answer:
5 miles per hour
Explanation:
if you divide 15 by 3 you get 5, therefore the student is going 5 miles per hour.
Answer:
It traveled 4 centimeters.
Explanation:
In a speed versus time graph, the distance travelled is given by the area under the graph.
In this graph we have the following:
- The speed of the object is v = 1 cm/s between time t = 0 s and t = 4 s
- The speed of the object is v = 0 cm/s between time t = 4 s and t = 8 s
Since the speed in the second part is zero, the distance travelled in the second part is zero. So, the only distance travelled by the object is the distance travelled during the first part, which is equal to the area of the first rectangle:

When developing an experimental design, the action that would improve the quality of the results is to ensure that it answers a question about cause and effect.
<h3>What is experimental design?</h3>
Experimental design is a concept used to organize, conduct, and interpret results of experiments in an efficient way, making sure that as much useful information as possible is obtained by performing a small number of trials.
Thus, when developing an experimental design, the action that would improve the quality of the results is to ensure that it answers a question about cause and effect.
Learn more about experimental design here: brainly.com/question/17274244
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