Calculating Charge on Suspended Spheres using Coulomb's Law

In summary, two identical small spheres with a mass of 2.0g are attached to a 0.60m long insulating thread and suspended from the ceiling. They are given the same electric charge and are in static equilibrium with an angle of 30.0 degrees between the two halves of the thread. Using Coulomb's Law and a free body diagram, the magnitude of the charge on each sphere can be calculated by finding the force needed to cancel out the gravity acting on the spheres.
  • #1
preet
98
0
"Two identical small spheres of mass 2.0g are fastened to the ends of an insulating thread of length 0.60m. The spheres are suspended by a hook in the ceiling from the centre of the thread. The spheres are given identical electric charges and hand in static equilibrium, with an angle of 30.0 degrees between the string halves. Calculate the magnitude of the charge on each sphere."

What I've done so far...
The length of each part of string connected to each ball is 0.3m. The distance between the two masses is 0.076 approximately. That's all I can think of... I have the distance and the constant for Coulomb's Law. That still leaves me with two variables... (electrical force and charge). Where do I go from here? TiA
 
Physics news on Phys.org
  • #2
You need to do a free body diagram to identify the forces acting on the charge spheres.
 
  • #3
You know that the force between the balls is enough to keep them in equilibrium with gravity. Find out how much of the force is needed to cancel out the gravity. With that you can find the force and then the charge.
 

FAQ: Calculating Charge on Suspended Spheres using Coulomb's Law

What is Coulomb's Law?

Coulomb's Law is a fundamental law of electrostatics that describes the attraction or repulsion between two charged particles. It states that the force between two charges is directly proportional to the product of their magnitudes and inversely proportional to the square of the distance between them.

What are the units of Coulomb's Law?

The units of Coulomb's Law are Newtons per Coulomb squared (N/C^2) or, equivalently, Joules per Coulomb (J/C).

How does distance affect the force in Coulomb's Law?

According to Coulomb's Law, the force between two charges decreases as the distance between them increases. This relationship is described by the inverse square law, meaning that the force is inversely proportional to the square of the distance between the charges.

Can Coulomb's Law be applied to both positive and negative charges?

Yes, Coulomb's Law can be applied to both positive and negative charges. The sign of the charges will determine whether the force between them is attractive or repulsive.

What is the significance of Coulomb's constant in Coulomb's Law?

Coulomb's constant, also known as the electric constant, is a fundamental constant of nature that relates the strength of the electric force to the properties of the charges involved. It is represented by the symbol k and has a value of approximately 8.99 x 10^9 Nm^2/C^2.

Similar threads

Use of imaginary charge vs Gauss' law
Replies
12
Views
461
Coulomb's law to find electric field for charge density function
Replies
11
Views
641
Angle between 2 charged spheres hanging from string
Replies
19
Views
6K
Question regarding Coulomb's Law
Replies
8
Views
1K
Find the magnitude of the electric force from 3 charges at vertices of a cube
Replies
17
Views
2K
Using Gauss' Law to find the field at a point
Replies
6
Views
1K
Calculating Charge and Force Using Coulomb's Law and Trigonometry
Replies
6
Views
8K
Find the electric field on the surface of a sphere using Coulomb's law
Replies
6
Views
1K
How Do You Calculate the Electric Charge on a Suspended Cork Ball?
Replies
2
Views
2K
Electric field at a point inside a non-uniformly charged sphere
Replies
6
Views
740

Hot Threads

Recent Insights

Back
Top