The electric field intensity generated by a single point charge is given by
where
k is the Coulomb's constant
q is the charge
r is the distance from the charge
In this problem, the charge is 
and we are asked to calculate the field at distance 
, so the electric field is
Answer: A. 200J
Therefore, the workdone by the heat engine is 200J
Explanation:
Given ;
The efficiency of the heat engine is E = 20% = 0.2
Heat loss L= 800J
For an heat engine the efficiency is measured by the amount of workdone by the heat engine when compared to the heat generated.
Efficiency E = workdone/heat generated × 100%
Heat generated G= workdone W + heat loss L
G = W + L
According to the question.
W = 20% of G
W = 0.2G ......1
L = 80% of G
L = 0.8G
G = L/0.8 ......2
Substituting equation 2 to 1
W = 0.2(L/0.8)
And L = 800J
W = 0.2(800/0.8)
W = 200J
Therefore, the workdone by the heat engine is 200J
She benefits from products that use minerals found using geological maps.
Answer:
A real emf device has an internal resistance, but an ideal emf device does not.
The general accepted value of acceleration due to gravity, g, is 9.81 m/s^2.
That is an approximation because being the acceleration of gravity due to the attraction of the earth its magnitude will depend on the distance from the point to the center of the planet Earth.
The value of g is determined by using the Newton's Universal Law of gravity:
F = G * m of Earth * m of body / (distance^2)
Wehre {G* m of Earth / (distance^2) } = g
G is a universal constant = 6.67 * 10 ^ -11 N*m^2 / kg^2
m of Earth = 5.98 * 10 ^ 24 kg
distance = radius of Earth + height of the body
Given the the Earth is not a perfect sphere the radius varies. Also the height of the body varies.
If you take a mean radius of Earth of 6.37*10^6 m
you get
g = 6.67*10^-11 N*m^2/kg^2 * 5.98*10^24kg / (6.37*10^6 m)^2 = 9.83 m/s^2
Again, if you want a more precise value of g, you need to find the exact place where you are and then use the right r.
