Answer:
1) El diámetro es de aproximadamente 913,987 cm.
2) La fuerza del cilindro es 5576850 kgf
Explanation:
1) Los parámetros dados son;
El volumen del aire = 13,122 litros = 13122000 cm³
La presión de trabajo = 8.5 kgf / cm²
La longitud del cilindro = 20 cm.
Por lo tanto, tenemos;
El área de la base del cilindro = π · r² = 13122000 cm³ / (20 cm) = 656100 cm²
r = √ (656100 / π) ≈ 456,994 cm
El diámetro = 2 × r ≈ 2 × 456.994 ≈ 913.987 cm
El diámetro ≈ 913,987 cm
2) La fuerza del cilindro = El área de la base del cilindro × La presión de trabajo
∴ La fuerza del cilindro = 656100 cm² × 8.5 kgf / cm² = 5576850 kgf
La fuerza del cilindro = 5576850 kgf
g Generally the accepted value of acceleration due to gravity is 9.801 
as per the question the acceleration due to gravity is found to be 9.42
in an experiment performed.
the difference between the ideal and observed value is 0.381.
hence the error is -
=3.88735 percent
the error is not so high,so it can be accepted.
now we have to know why this occurs-the equation of time period of the simple pendulum is give as-![T=2\pi\sqrt[2]{l/g}](https://tex.z-dn.net/?f=T%3D2%5Cpi%5Csqrt%5B2%5D%7Bl%2Fg%7D)

As the experiment is done under air resistance,so it will affect to the time period.hence the time period will be more which in turn decreases the value of g.
if this experiment is done in a environment of zero air resistance,we will get the value of g which must be approximately equal to 9.801 
When two forces act in the same direction, they add together. ... Equal forces acting in opposite directions are called balanced forces. Balanced forces acting on an object will not change the object's motion. When you add equal forces in opposite direction, the net force is zero.
Thinking the small glass bead as a single point charge, the electric field generated by it is given by

where

is the Coulomb's constant

is the charge of the bead

is the distance at which we calculate the field.
Using these data, we find: