Kelley and Raul are moving a 95 kg desk to the right. If the coefficient of friction between the desk and the floor is 0.29, what is the force of friction that will oppose the
motion of the desk?

Glass is transparent to visibile light under normal conditions; however, at extremely high intensities, glass will absorb most of the light incident upon it. this works through a process known as multiphoton absorption. in this process, several photons are absorbed at the same time. if very intense light whose photons carry 2ev of energy is shined onto a material with a band gap of 4ev, that light can be absorbed through two-photon absorption, because two photons have the right amount of energy to bridge the band gap. what is the minimum number of photons of 800-nm light that are needed to equal or exceed the band gap of fused silica glass

When the force acting on an object points at least partially in the direction of the motion the work done is considered to be negative

Why should seat belts not be mandatory quick plz