Calculate the period of a ball tied to a string of length 0.504 m making 3.9 revolutions every second. answer in units of s. your answer must be within ± 2.0% 004 (part 2 of 2) 10.0 points calculate the speed of the ball. answer in units of m/s. your answer must be within ± 2.0%

Consider a hydrogen atom in the ground state. what is the energy of its electron? =e= jj now consider an excited‑state hydrogen atom. what is the energy of the electron in the =5n=5 level? =e5= j

What is the thinnest soap film (excluding the case of zero thickness) that appears black when illuminated with light with a wavelength of 480 ? the index of refraction of the film is 1.34, and there is air on both sides of the film. express your answer in nanometers. hint 1. how to approach th

An object dropped from cliff falls with a constant acceleration of 10 metre per second square find its speed of two seconds after it was dropped