Q. 19

# One end of a 10 c

Given:

Mass of ball=10g

Charge of ball=4.0× 10-6C

Equilibrium angle of thread with vertical=60°

Let the surface charge density on the plate be σ

The forces acting on the ball are

• Weight of the ball downwards (W=mg)

Where m=mass of ball

g=acceleration due to gravity

• Electric force due to non-conducting plate producing electric field E (F=qE)

Where q=charge of the ball

E=electric field intensity

• Tension force (T) due to string at an angle of 60° from vertical

Electric field due to a thin non-conducting plate of surface charge density σ is given by

……(i)

The tension force T due to string is divided into horizontal and vertical components given by Tsin60° and Tcos60°

Since the ball is in equilibrium, the net horizontal and vertical force on the ball is zero

Applying equilibrium along horizontal direction, we get

…(ii)

Similarly, applying equilibrium along vertical direction, we get

….(iii)

Dividing eqn. (ii) by (iii)

Putting the value of E from eqn.(i), we get,

Putting the values of ϵ0,m,g and q in the above equation

C/m2

Therefore the surface charge density on the plate is given by 7.5× 10-7C/m2

Rate this question :

How useful is this solution?
We strive to provide quality solutions. Please rate us to serve you better.
Try our Mini CourseMaster Important Topics in 7 DaysLearn from IITians, NITians, Doctors & Academic Experts
Dedicated counsellor for each student
24X7 Doubt Resolution
Daily Report Card
Detailed Performance Evaluation
view all courses
RELATED QUESTIONS :

A long cylindricaHC Verma - Concepts of Physics Part 2

Two large conductHC Verma - Concepts of Physics Part 2

Consider the situHC Verma - Concepts of Physics Part 2

A nonconducting sHC Verma - Concepts of Physics Part 2

Consider the follHC Verma - Concepts of Physics Part 2

One end of a 10 cHC Verma - Concepts of Physics Part 2

A charge Q is plaHC Verma - Concepts of Physics Part 2

The electric fileHC Verma - Concepts of Physics Part 2

A charged particlHC Verma - Concepts of Physics Part 2

A long cylindricaHC Verma - Concepts of Physics Part 2