(ii) a woman stands on a bathroom scale in a motionless elevator. when the elevator begins to move, the scale briefly reads only 0.75 of her regular weight. calculate the acceleration of the elevator, and find the direction of acceleration.

Using software, a simulation of a javelin being thrown both on earth and on the moon is created. in both cases, the velocity and angle of projection are kept the same. on earth, the javelin covers a distance y. what distance would it cover on the moon? (the moon’s gravity is about 1/6th that of earth.) a. 6y b. 6/y c. y/6 d. (y+6)2

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.

Aspring has a natural length of 8 m. if a 12-n force is required to keep it stretched to a length of 10 m, how much work w is required to stretch it from 8 m to 16 m? (round your answer to two decimal places.)