An electron collides with an atom in its ground state at rest. The atom then emits a photon of energy $E_{photon}$. In this process,the change $\Delta E_{elec}$ in the electron's energy is

The hybrids are generally found to be superior to their parents; this is because of:

The number of solutions of the equation $4 \cos 2 \theta \cdot \cos 3 \theta = \sec \theta$,when $0 < \theta < \pi$,is

Vernalization stimulates flowering in

In a compound microscope,the focal lengths of the objective and the eye lens are $2.5 \, cm$ and $5 \, cm$ respectively. An object is placed at $3.75 \, cm$ before the objective and the image is formed at the least distance of distinct vision. Then,the distance between the two lenses (i.e.,the length of the microscope tube) will be......$cm$.

The point where the line $\frac{x - 1}{2} = \frac{y - 2}{-3} = \frac{z + 3}{4}$ meets the plane $2x + 4y - z = 1$ is: