If earth suddenly stops rotating, how will the 'Acceleration due to Gravity' change?

What are similarities and differences between refraction, reflection, diffraction and absorption?

Why should the wavelength scale of spectroscope be calibrated

Acircular ring of charge with radius b has total charge q uniformly distributed around it. what is the magnitude of the electric field at the center of the ring? 0 keq/b2 keq2/b2 keq2/b none of these answers