Which of the following is NOT true?

The correct answer is Option (2) → One of the conclusions of Maxwell’s equations was the existence of gravitational waves.

Option (1) Maxwell formulated a set of equations, known as Maxwell’s equations, involving electric and magnetic fields and their sources. — True. The sources in these equations are the charge and current densities. Together with the Lorentz force formula, they express all the basic laws of electromagnetism.

Option (2) One of the conclusions of Maxwell’s equations was the existence of gravitational waves. — Not true. Maxwell’s equations deal only with electric and magnetic fields and their sources. Their most important prediction was the existence of electromagnetic waves. These are coupled time-varying electric and magnetic fields that travel through space. Gravity has no place in these equations.

Option (3) The concept of Maxwell’s displacement current removed the inconsistency in Ampere’s circuital law. — True. For a charging capacitor, the law gave different fields for different surfaces with the same rim. Adding the displacement current \( \varepsilon_0\,d\Phi_E/dt \) gives the same total current through every such surface.

Option (4) Maxwell’s equations led to the conclusion that light is an electromagnetic wave. — True. The speed of the predicted waves came out very close to the measured speed of light, \( 3\times10^{8}\,\mathrm{m\,s^{-1}} \).

NCERT (2026-27):
Introduction – “The most important prediction to emerge from Maxwell’s equations is the existence of electromagnetic waves, which are (coupled) time-varying electric and magnetic fields that propagate in space.”