When one of the electrons of a particular atom undergoes a transition to a quantum state of lower energy, it: a. collides with another of its electrons
b. exchanges quantum states with another of its electrons
c. undergoes a transition to a quantum state of higher energy
d. emits a photon of light

Aprojectile is launched horizontally 10m above the ground and with an initial velocity of 15 m/s. a) sketch the trajectory using an appropriate coordination system. b) how long for the projectile to reach the ground. c) how far did projectile travel horizontally before striking the ground. d) determine the projectilex & y position at t-1.3s e) determine the magnitude and direction of projectile velocity at t= 1.3s f) determine the magnitude and direction of projectile acceleration at t-1.3s

In a voltaic cell, electrons flow from the (positive/negative) to the (positive/negative) terminal.

Which of the following situations is impossible? a) an object has velocity directed east and acceleration directed east. b) an object has zero velocity but non-zero acceleration. c) an object has constant non-zero velocity and changing acceleration. d) an object has velocity directed east and acceleration directed west. e) an object has constant non-zero acceleration and changing velocity.