Class 12 Physics: Electrostatics

Which of the following statements accurately describes the relationship between electric charge and Coulomb's Law?

Two point charges, +q and +4q, are separated by a distance r. What can be said about the force on each charge?

If the distance between two point charges is doubled, how does the electrostatic force between them change?

What is the primary focus of the branch of physics known as electrostatics?

Which of the following values represents the approximate magnitude of the elementary charge 'e'?

A parallel plate capacitor has a capacitance $C_0$ with air as the dielectric. If a dielectric material of constant $K$ is inserted to fill half the space between the plates, what is the new capacitance?

A wire of resistance $R$ is stretched to double its original length. Assuming that the density and resistivity of the material remain unchanged, what will be the new resistance of the wire?

In a Wheatstone bridge, three resistors are connected in a loop configuration. At what state there will be balanced condition?

What is the effect of increasing the temperature on the resistivity of semiconductors and metals?

A proton enters a uniform magnetic field at right angles to the field. What is the nature of the subsequent path of the proton?

A galvanometer can be converted into a voltmeter by using which of the following methods?

Using Kirchhoff's Laws, which of the following statements is correct for a simple closed-loop circuit containing multiple resistors and voltage sources?

Two parallel wires carry currents in opposite directions. What is the nature of the force between them?

A magnetic dipole is placed in a uniform magnetic field. In which orientation will the potential energy of the dipole be maximum?

What happens to the capacitance of a parallel plate capacitor when the area of the plates is doubled and the distance between the plates is halved?

A conducting rod is moving through a uniform magnetic field. Which of the following factors does NOT affect the magnitude of the motional EMF induced in the rod?

In an LCR series circuit connected to an AC source, the voltage across the inductor is $V_L$, the voltage across the capacitor is $V_C$, and the voltage across the resistor is $V_R$. If $V_L = 40V$, $V_C = 70V$, and $V_R = 40V$, what is the effective voltage of the AC source?

Which of the following statements is MOST accurate regarding the displacement current introduced by Maxwell?

When light travels from air into water, which of the following properties of light remains unchanged?

A beam of light is incident on a glass-air interface. Which condition is necessary for total internal reflection to occur?

According to Huygens' principle, how does a wavefront propagate through a medium?

In a Young's double-slit experiment, what change would cause the fringe width to increase?

What is the effect on the kinetic energy of photoelectrons if the intensity of incident light on a metal surface is doubled, while the frequency remains above the threshold frequency?

An electron and a proton have the same de Broglie wavelength. Which of the following is true about their momenta?

In the Bohr model of the hydrogen atom, what quantity is quantized?

What happens to the binding energy per nucleon as the mass number increases beyond approximately A=60?

If the half-life of a radioactive substance is 30 years, approximately what percentage of the original sample will remain after 90 years?

What is the primary difference between an intrinsic and an extrinsic semiconductor?

In a common emitter transistor amplifier, what is the phase difference between the input signal and the output signal?

Which type of electromagnetic wave propagation is MOST suitable for long-distance communication that follows the curvature of the Earth?