a space probe with a mass of 4000 kg expels 3,500 of its mass at a velocity of 2000 m/s. what is the velocity of the remaining 500 kg of the probe

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

What are similarities and differences between refraction, reflection, diffraction and absorption?

Which governments provide garbage collection services to homes and businesses