To resolve an object in an electron microscope, the wavelength of the electrons must be close to the diameter of the object.
What kinetic energy, K. E, must the electrons have in order to resolve a protein molecule that is 4.50 nm in diameter? Take the mass of an electron to be 9.11×10^(−31) kg.

John throws .4 kg ball with velocity of 18 m/s. hits .2 kg bottle and bottle flies 25 m/s. how fast is ball traveling after hitting the bottle?

30 points - when can a theory be modified if a new type of technology allows for new observations that raise new questions? a. immediately, while the questions about the theory are being asked b. after new hypotheses related to the theory are tested in experiments c. only after the new observations disprove all parts of the theory d. while scientists begin to think about how the theory could improve

If element x has 99 protons how many electrons does it have