Electric field and gravitational field question

The answer key might be rounding differently.In summary, the conversation discusses the comparison of electric and gravitational forces between two oxygen atoms treated as point particles. The attempt at a solution involves calculating the forces using the given equations and determining that the net force is attractive. However, there may be discrepancies in the numerical answer due to rounding.
  • #1
strawberrysk8
27
0

Homework Statement



making the worst possible combination of errors, an oxygen atom has a charge of 3.8x10^-39C. Treating the atoms as point particles, compare eletric force of two such oxygen atoms with gravitational force between atoms. is the net force repulsive or attractive?


Homework Equations



F = kqq/r^2

F = GmM/r^2

1 amu = 1.66x10^-27 kg


The Attempt at a Solution



oxygen atom = 32 amu

32 amu * (1.66x10^-27 kg) = 5.31x10^-26 kg

F(electric) = [ (9x10^9) * (3.8x10^-39)^2 ] / r^2

F(gravity) = [ (6.67x10^-11) * (5.31x10^-26 kg)^2 ] / r^2

F(gravity)/F(eletric) = 1.4x10^6

attractive because F(gravity) > F(electric)


but according to the answer key the answer should be 2.8x10^6
what am I doing wrong?
 
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  • #2
I don't see anything wrong. Furthermore the question doesn't even ask for any numerical answer, only which force is greater.
 
  • #3
I think you mean oxygen molecule (32 amu), not atom (16 amu). But even so, I don't find anything terribly wrong with your ratio.
 

1. What is the difference between an electric field and a gravitational field?

The main difference between an electric field and a gravitational field is that an electric field is created by electric charges, while a gravitational field is created by mass. Electric charges interact with each other through the electric field, while mass interacts with each other through the gravitational field.

2. How are electric fields and gravitational fields similar?

Both electric fields and gravitational fields are forms of force fields that extend through space and have an effect on objects within their range. They both follow the inverse-square law, meaning that the strength of the field decreases with the square of the distance from the source.

3. How are electric and gravitational forces related?

Electric and gravitational forces are both types of fundamental forces in nature. While electric forces act on electric charges and gravitational forces act on mass, they both follow the same mathematical principles and can be described by similar equations. Additionally, both forces can be attractive or repulsive.

4. Can electric and gravitational fields overlap?

Yes, electric and gravitational fields can overlap and coexist in the same space. This can be seen in many real-life scenarios, such as with charged particles in Earth's gravitational field or with charged planets in the gravitational field of a star.

5. How can the strength of an electric or gravitational field be measured?

The strength of an electric field can be measured using a device called an electric field meter, which measures the force experienced by a test charge placed in the field. The strength of a gravitational field can be measured using a device called a gravimeter, which measures the acceleration of a test mass placed in the field.

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