The formula of sodium nitroprusside is .........

Which of the following is a true acidic anhydride?

The following diagram indicates the energy levels of a certain atom. When the system moves from the $4E$ level to the $E$ level, a photon of wavelength $\lambda_1$ is emitted. The wavelength of the photon produced during its transition from the $\frac{7}{3}E$ level to the $E$ level is $\lambda_2$. The ratio $\frac{\lambda_1}{\lambda_2}$ will be:

$A$ ray of light is incident upon an air/water interface (it passes from air into water) at an angle of $45^o$. Which of the following quantities change as the light enters the water?
$(I)$ wavelength
$(II)$ frequency
$(III)$ speed of propagation
$(IV)$ direction of propagation

Two springs have spring constants $K_A$ and $K_B$ such that $K_A > K_B$. If both springs are stretched by the same extension $x$,the work required will be:

The pair not correctly matched is