What forces must be balanced in the bohr model? a. electron attraction between electron and nucleus = centripetal force of the orbiting electronb. electrostatic repulsion of particles in the nucleus = electrostatic attraction between electrons and protonsc. electron attraction between electron and nucleus = electrostatic attraction between electrons and protonsd. none of the above

The energy of a photon was found to be 3.38 × 10–19 j. planck’s constant is 6.63 × 10–34 j • s. which color of light corresponds to this photon?

Samir watches a 100-minute movie on his spaceship. maria's spaceshipe flies in the same direction as samir's spaceship but she observes his move to last 125 minutes and his spaceship to be 40 m long. how long does samir observe his own spaceship to be? according to an observer on earth, planet x is stationary. maria and samir depart earth on their spaceships at the same time, each flying at 0.5c. maria flies toward planet x and samir flies in the opposite direction. according to maria, her voyage to planet x takes 9 years. how many years does marias voyage take according to samir?

Suppose you increase your walking speed from 7 m/s to 13 m/s in a period of 2 s. what is your acceleration?