Assume (unrealistically) that a TV station acts as a point source broadcasting isotropically at 1.9 MW. What is the intensity of the transmitted signal reaching a nearby star that is 39 ly away. (An alien civilization at that distance might be able to watch X Files.) A light-year (ly) is the distance light travels in one year.

Why does the equilibrium position of the spring change when a mass is added to the spring? will the mass oscillate around the new equilibrium position of the spring or the previous position without a mass attached to the spring? if the equilibrium position of the spring changes by 20 cm (assuming no initial mass) when a mass is added to the spring with constant 4.9 kg/s^2, what is the mass of the object attached to the spring?