The a-36 steel bolt is tightened within a hole so that the reactive torque on the shank ab can be expressed by the equation t = (kx2) n. m/m, where x is in meters. if a torque of t = 50 n. m is applied to the bolt head, determine the constant k and the amount of twist in the 50-mm length of the shank. assume the shank has a constant radius of 4 mm. the shear modulus of elasticity for a-36 steel is 75 gpa.

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.

Amira pulls a 3 pound wagon 4 feet. how much work has she done?

Acar travels 40m in 8 seconds find the car speed