A tennis ball moving with velocity v1 hits a stationary tennis ball. The collision is inelastic and the two balls start travelling together. What is the velocity of the two tennis balls moving together?

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

When a vertical beam of light passes through a transparent medium, the rate at which its intensity i decreases is proportional to i(t), where t represents the thickness of the medium (in feet). in clear seawater, the intensity 3 feet below the surface is 25% of the initial intensity i0 of the incident beam. what is the intensity of the beam "10" feet below the surface? (give your answer in terms of i0. round any constants or coefficients to five decimal places.)

If you place a magnet under a clear dish, and sprinkle iron fillings over it, above what part of the magnet will most of the fillings gather