:<span> </span><span>Under the assumption that a cell is made up of two concentric spheres you find the surface are of the inside sphere which will be your A.
You already have your separation and dielectric constant so just use the formula you stated towards the end of your question and you get 8.93x10^-11 Farads which is about 89pF</span>
Using lens equation;
1/o + 1/i = 1/f; where o = Object distance, i = image distance (normally negative), f = focal length (normally negative)
Substituting;
1/o + 1/-30 = 1/-43 => 1/o = -1/43 + 1/30 = 0.01 => o = 1/0.01 = 99.23 cm
Therefore, the object should be place 99.23 cm from the lens.
Answer:
Current = 8696 A
Fraction of power lost = 
= 0.151
Explanation:
Electric power is given by
where I is the current and V is the voltage.
Using values from the question,
The power loss is given by
where R is the resistance of the wire. From the question, the wire has a resistance of 
per km. Since resistance is proportional to length, the resistance of the wire is
Hence,
The fraction lost = 
Answer:
Left
Explanation:
newtons is a measure of force. Since there is more newtons(force) pushing to the left, the object will move left. the 15 newtons cancel each other out, leaving only 5 newtons pushing to one side with no resistance.
