Electrostatic and Other IMP Chapters - MHT-CET Physics

Electrostatics, Gravitation, and Current Electricity: Key Formulas and Exam Questions

Types and Properties of Charge Electric charge exists in two types: positive and negative. Like charges repel, unlike charges attract. The force between charges is called the electrostatic force, which can be attractive or repulsive depending on the...

If a positive test charge is placed in an electric field, in which direction does it experience force?

In the direction of the electric field

What is the formula for the electric field at a distance r from a point charge q in vacuum?

E = 1/(4πε₀) × q/r²

If a positive test charge is placed in an electric field, in which direction does it experience force?

In the direction of the electric field

What is the formula for the electric field at a distance r from a point charge q in vacuum?

E = 1/(4πε₀) × q/r²

What is the fundamental principle of a potentiometer, and how is it mathematically expressed when comparing voltages?

The core principle of a potentiometer is balancing an unknown voltage with a known potential difference. This implies that the potential difference across a wire is directly proportional to its length, $V \propto L$. When comparing two voltages, this leads to the relation $\frac{V_1}{V_2} = \frac{L_1}{L_2}$.

What formula is used to determine the shunt resistance $S$ when converting a galvanometer with resistance $G$ into an ammeter, given the galvanometer current $I_G$ and the total main current $I$?

The formula for shunt resistance $S$ is $\frac{I_G}{I} = \frac{S}{S+G}$. This low resistance $S$ is connected in parallel with the galvanometer to allow most of the main current to bypass the galvanometer.