Conversion fraction 1$=4q, how many are in 20$

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?

The dominant wavelength of energy emitted by the sun is

Estimate the magnitude of the electric field due to the proton in a hydrogen atom at a distance of 5.29×10 to the power of −11 m, the expected position of the electron in the atom.