Coulomb's Law (Electric Force) Video Lessons

Concept

# Problem: A positively charged particle Q1 = +45 nC is held fixed at the origin. A second charge Q2 of mass m = 7.5 μg is floating a distance d = 25 cm above charge Q1. The net force on Q2 is equal to zero. You may assume this system is close to the surface of the Earth.(a) What is the sign of the charge on Q2?(b) Write an equation for the magnitude of charge Q2 in terms of the given variables.(c) Calculate the magnitude of Q2 in units of nanocoulombs.

###### FREE Expert Solution

(a)

The second charge floats if it is repelled by the first charge.

According to the basic law of electrostatics, like charges repel while unlike charges attract.

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###### Problem Details

A positively charged particle Q1 = +45 nC is held fixed at the origin. A second charge Q2 of mass m = 7.5 μg is floating a distance d = 25 cm above charge Q1. The net force on Q2 is equal to zero. You may assume this system is close to the surface of the Earth.

(a) What is the sign of the charge on Q2?

(b) Write an equation for the magnitude of charge Q2 in terms of the given variables.

(c) Calculate the magnitude of Q2 in units of nanocoulombs.

What scientific concept do you need to know in order to solve this problem?

Our tutors have indicated that to solve this problem you will need to apply the Coulomb's Law (Electric Force) concept. You can view video lessons to learn Coulomb's Law (Electric Force). Or if you need more Coulomb's Law (Electric Force) practice, you can also practice Coulomb's Law (Electric Force) practice problems.