A moving electron passes near the nucleus of a gold atom, which contains 79 protons and 118 neutrons. At a particular moment the electron is a distance of 7.5 × 10−9 m from the gold nucleus.

What is the magnitude of the force exerted by the gold nucleus on the electron?

I seem to recall answering this already.

F = k*Q1*Q2/R^2 = 79k*e^2/R^2

(Coulomb's law; k = Coulomb's constant)

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I'm not getting the answer using this formula. Can you explain it a little more. Thanks

To find the magnitude of the force exerted by the gold nucleus on the electron, we can use Coulomb's law. Coulomb's law states that the force between two charged particles is directly proportional to the product of their charges, and inversely proportional to the square of the distance between them.

Here are the steps to calculate the magnitude of the force:

1. Determine the charge of the gold nucleus: The gold nucleus contains 79 protons, each with a charge of +1.6 × 10^(-19) C. So the total charge of the gold nucleus is (79 protons) × (+1.6 × 10^(-19) C/proton).

Total charge = 79 × (+1.6 × 10^(-19) C)

2. Calculate the distance between the electron and the gold nucleus: The distance is given as 7.5 × 10^(-9) m.

Distance = 7.5 × 10^(-9) m

3. Calculate the magnitude of the force using Coulomb's law:

Magnitude of force = (k × |charge1 × charge2|) / distance^2

where k is the electrostatic constant (9 × 10^9 N•m²/C²) and |charge1| and |charge2| are the absolute values of the charges of the electron and the gold nucleus, respectively.

Magnitude of force = (9 × 10^9 N•m²/C²) × (|charge of electron| × |charge of gold nucleus|) / distance^2

Plug in the values:

Magnitude of force = (9 × 10^9 N•m²/C²) × [(+1.6 × 10^(-19) C) × (79 × (+1.6 × 10^(-19) C))] / (7.5 × 10^(-9) m)^2

Simplify the expression using multiplication and division:

Magnitude of force = (9 × 10^9 N•m²/C²) × (1.6 × 10^(-19) C) × (79 × 1.6 × 10^(-19) C) / (7.5 × 10^(-9) m)^2

Now, evaluate the expression using a calculator to get the numerical value of the magnitude of the force.