/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 12 How many electrons must be rem... [FREE SOLUTION] | 91Ó°ÊÓ

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How many electrons must be removed from each of two 5.0 -kg copper spheres to make the electric force of repulsion between them equal in magnitude to the gravitational attraction between them?

Short Answer

Expert verified
Answer: Approximately 9.64 × 10^10 electrons must be removed from each sphere.

Step by step solution

01

Write down the relevant formulas.

First, we write down the formulas for the gravitational force (F_gravity) and the electric force (F_electric). F_gravity = G * (m1 * m2) / r^2 F_electric = k * (q1 * q2) / r^2 where G is the gravitational constant (6.674 × 10^-11 N m^2/kg^2), m1 and m2 are the masses of the copper spheres, k is the electrostatic constant (8.99 × 10^9 N m^2/C^2), q1 and q2 are the charges on the copper spheres, and r is the distance between the centers of the spheres. We are given that the spheres have a mass of 5.0 kg each, so m1 = m2 = 5.0 kg, and we want the forces to have equal magnitudes: F_gravity = F_electric.
02

Equate the magnitudes of the forces and solve for the charge.

To find the number of electrons, we first need to find the charge needed on each sphere. We equate the magnitudes of the gravitational and electric forces and solve for q1 * q2: G * (m1 * m2) / r^2 = k * (q1 * q2) / r^2 By cancelling out r^2 and rearranging the equation, we get: q1 * q2 = G * (m1 * m2) / k Since the charges on the copper spheres have the same magnitude (q1 = q2), we can substitute q^2 for q1 * q2: q^2 = G * (m1 * m2) / k Now we can solve for q: q = sqrt(G * (m1 * m2) / k)
03

Calculate the value of the charge.

By plugging the given values and constants into the equation, we can calculate the charge: q = sqrt((6.674 × 10^-11 N m^2/kg^2) * (5.0 kg * 5.0 kg) / (8.99 × 10^9 N m^2/C^2)) q ≈ 1.54 × 10^-8 C
04

Calculate the number of electrons.

Now we know the total charge needed on each sphere, we can find the number of electrons that must be removed. The charge of an individual electron is 1.60 × 10^-19 C. We divide the charge on each sphere by the charge of an electron to find the number of electrons: number of electrons = q / e number of electrons = (1.54 × 10^-8 C) / (1.60 × 10^-19 C) number of electrons ≈ 9.63 × 10^10 Since we cannot have a fraction of an electron, we will round up to the nearest whole number: Number of electrons to be removed from each sphere ≈ 9.64 × 10^10

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Most popular questions from this chapter

A coaxial cable consists of a wire of radius \(a\) surrounded by a thin metal cylindrical shell of radius \(b\). The wire has a uniform linear charge density \(\lambda>0\) and the outer shell has a uniform linear charge density \(-\lambda\). (a) Sketch the field lines for this cable. (b) Find expressions for the magnitude of the electric field in the regions \(r \leq a, a
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