Last Updated on August 2, 2024 by XAM CONTENT
Hello students, here you will find numerical on superposition principle with answers. Before we start solving the numerical, let’s see some important points and formulae. This will help you to solve the problems efficiently.
Understanding Superposition Principle
Imagine tiny, charged balls that attract or repel each other with a certain force. This force depends on how strong each ball’s charge is and how far apart they are (closer = stronger force, like magnets).
Coulomb’s law helps us calculate this force between just two balls. But what if there are more than two?
Here’s where the cool principle of superposition comes in. It basically says that each charged ball acts independently. The force it exerts on another ball isn’t affected by the presence of other charged balls nearby. So, to find the total force on a single ball, we can simply add up the individual forces from each of the other balls, one at a time.
Think of it like playing tug-of-war with multiple ropes. The pull you feel from each rope (charged ball) adds together to give you the overall pull (total force).
Superposition Principle: Force between multiple charges
Let point charges q1, q2, q3 ……….. qN are placed at the position r1, r2, r3 ………. rN respectively.
According to principle of superposition the net force one charge is the vector some of all the forces due to other charges.
The total force on charge q1 is given by,
Superposition principle states that “The total force on a given charge is the vector sum of the forces exerted on it due to all other charges.”
In the below section, we are providing numerical problems based on Superposition Principle of Electric Forces for Class 12 Physics.
Superposition Principle of Electric Forces Class 12 Physics Numerical with Answers
Formula used:
Units used:
Forces are in newton, charges in coulomb and distances in metre.
Question 1: Consider three charges q1, q2, q3 each equal to q at the vertices of an equilateral triangle of side L. What is the force on a charge Q (with the same sign as q) placed at the centroid of the triangle?
Ans. The total force on charge Q is zero.
Question 2: Three point charges +q each are kept at the vertices of an equilateral triangle of side ‘l’. Determine the magnitude and sign of the charge to be kept at its centroid so that the charges at the vertices remain in equilibrium.
Ans. – q/√3
Question 3: Four equal point charges each 16 μC are placed on the four corners of a square of side 0.2 m. Calculate the force on any one of the charges.
Ans. 110.3 N, along BD produced.
Question 4: Three point charges of +2 μC, -3 μC and -3 μC are kept at the vertices A, B and C respectively of an equilateral triangle of side 20 cm as shown in Fig. 1.30(a). What should be the sign and magnitude of the charge to be placed at the midpoint (M) of side BC so that the charge at A remains in equilibrium?
Ans. 2.34 N along AM
Question 5: An infinite number of charges each equal to 4 μC are placed along x-axis at x = 1 m, x = 2 m, x = 4 m, x = 8 m and so on. Find the total force on a charge of 1 C placed at the origin.
Ans. 4.8 x 104 N
We hope the given numerical on Superposition Principle of Electric Forces Class 12 Physics helps you in your learning.
For further practice on numerical problems related to Superposition Principle Class 12 Physics, we recommend exploring the link given below.
Frequently Asked Questions (FAQs) on Superposition Principle of Electric Forces Class 12 Physics
Q1: What is the superposition principle for electric charges?
A1: The superposition principle states that the total force experienced by a charged particle due to multiple other charged particles is the vector sum of the individual forces exerted by each particle, independent of the presence of the others.
Q2: How do we use the superposition principle?
A2: We can use Coulomb’s Law to find the force between two individual charges. Then, the superposition principle allows us to find the total force on a single charge by adding the forces from each other charge (vector sum) as if they were acting alone.
Q3: Does the order in which I add the forces matter?
A3: No, the order in which you add the forces does not matter when applying the superposition principle to electric charges. This is a fundamental aspect of the principle. Whether you sum the forces acting on a charge from multiple charges in a different order, you should arrive at the same total force. The principle states that the total force experienced by a charge is the vector sum of the individual forces exerted by each charge acting independently. Therefore, regardless of the sequence in which you consider the individual forces, the resultant force will be the same.
Q4: Does the superposition principle apply to all types of charges?
A4: Yes, the superposition principle applies to both positive and negative electric charges. Like charges repel, and unlike charges attract.
Q5: Can the superposition principle be applied to continuous charge distributions?
A5: Yes, the superposition principle can be applied to continuous charge distributions by dividing the distribution into infinitesimally small charge elements. By considering the contributions of each element, we can calculate the total electric force on a charge due to the continuous distribution.
Q6: Are there any limitations to the superposition principle?
A6: Yes, the superposition principle is strictly valid only for weak electric fields. At very high electric fields, non-linear effects become important, and the principle breaks down. For example, in certain nonlinear systems or materials, such as ferromagnetic materials, the principle may not apply directly due to interactions between charges altering the overall behavior.
