If $$\lambda$$₁ and $$\lambda$$₂ are the wavelengths of the third member of Lyman and first member of the Paschen series respectively, then the value of $$\lambda$$₁ : $$\lambda$$₂ is :

Find the gravitational force of attraction between the ring and sphere as shown in the diagram, where the plane of the ring is perpendicular to the line joining the centres. If $$\sqrt 8 $$R is the distance between the centres of a ring (of mass 'm') and a sphere (mass 'M') where both have equal radius 'R'.

Five equal resistances are connected in a network as shown in figure. The net resistance between the points A and B is :

A person standing on a spring balance inside a stationary lift measures 60 kg. The weight of that person if the lift descends with uniform downward acceleration of 1.8 m/s² will be ______________ N. [g = 10 m/s²]