Magnitude of the gravitational force of attraction between the proton & electron

AI Thread Summary
To find the gravitational force of attraction between a proton and an electron, use the formula F = GMm/r², where G is the gravitational constant (6.67 x 10^-11 N(m/kg)²), M is the mass of the proton, m is the mass of the electron, and r is the distance between them (2.8 meters). The values for the masses are 1.67 x 10^-27 kg for the proton and 9.11 x 10^-31 kg for the electron. The electric force equation F = kQq/r² is not applicable for gravitational calculations. The correct approach involves substituting the appropriate values into the gravitational formula. The discussion emphasizes the distinction between electric and gravitational forces.
ali13
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Homework Statement



A single proton and a single electron are fixed at a distance of 2.8 meters from each other. Find the magnitude of the electric force of attraction between them.

i have the answer to this, it is: 2.93*10^-29

but now it asks: Find the magnitude of the gravitational force of attraction between the proton and the electron. (Mass of a proton = 1.67 x 10-27 kg; Mass of an electron = 9.11 x 10-31 kg)

i'm not sure where to put gravity, 6.67 * 10^-11, in the equation:

F=k*Q*q/r2

thank you!
 
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hi ali13! welcome to pf! :smile:

(try using the X2 icon just above the Reply box :wink:)
ali13 said:
i'm not sure where to put gravity, 6.67 * 10^-11, in the equation:

F=k*Q*q/r2

F = GMm/r2 :wink:
 
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