Two water balloons of mass 0.35 kg collide and bounce off of each other
without breaking. before the collision, one water balloon moved at a velocity
of 2.5 m/s east, while the other moved at a velocity of 2.25 m/s west. after
the collision, one balloon moves at a velocity of 1.75 m/s west. what is the
velocity of the other water balloon?
o
a. 2 m/s west
o
b. 0.25 m/s east
o
c. 0.25 m/s west
o
d. 2 m/s east

Some material consisting of a collection of microscopic objects is kept at a high temperature. a photon detector capable of detecting photon energies from infrared through ultraviolet observes photons emitted with energies of 0.3 ev, 0.5 ev, 0.8 ev, 2.0ev, 2.5ev, and 2.8ev. these are the only photon energies observed. (a) draw and label a possible energy-level diagram for one of the microscopic objects, which has four bound states. on the diagram, indicate the transitions corresponding to the emitted photons. explain briefly. (b) would a spring–mass model be a good model for these microscopic objects? why or why not? (c) the material is now cooled down to a very low temperature, and the photon detector stops detecting photon emissions. next, a beam of light with a continuous range of energies from infrared through ultraviolet shines on the material, and the photon detector observes the beam of light after it passes through the material. what photon energies in this beam of light are observed to be significantly reduced in intensity (“dark absorption lines”)? explain briefly.

Examine the nuclear reacti why is this classified as a nuclear reaction rather than a chemical reaction? it is not balanced. a new compound is formed. a change has occurred in a nucleus. a new element has been formed.

More solar radiation is absorbed by earth’s surface than by