The transition from the state $n = 4$ to $n = 3$ in a hydrogen-like atom results in ultraviolet radiation. Infrared radiation will be obtained in the transition:

The radius of which of the following orbits is the same as that of the $1^{st}$ orbit of $H$ atom?

The current through the $1 \Omega$ resistance in the following circuit is (in $A$)

In green plants,cell elongation in the internodal regions is caused by which of the following?

Water is pumped from a depth of $10\, m$ and delivered through a pipe of cross section $10^{-2}\, m^2$. If it is needed to deliver a volume of $10^{-1}\, m^3$ per second,the power required will be: ............ $kW$

If the lines $x^2+2xy-35y^2-4x+44y-12=0$ and $5x+\lambda y-8=0$ are concurrent,then the value of $\lambda$ is