It has been suggested that solar powered space ships could get a boost from a laser either on Earth or in orbit around Earth. The laser would have to be very powerful to give any measurable benefit to the ship. If the laser produces a 0.1-m diameter beam of 446-nm light, what is the minimum angular spread of the beam?

A helium-neon laser produces a beam of diameter 1.75 mm, delivering 3.15 x 1018 photons/s. Each photon has a wavelength of 633 nm. (a) Calculate the amplitude of the electric field inside the beam. kv/m (b) Calculate the amplitude of the magnetic field inside the beam. μT (c) If the beam shines perpendicularly onto a perfectly reflecting surface, what force does it exert on the surface? nN (d) If the beam is absorbed by a block of ice at 0°C for 2.10 h, what mass of ice is melted? g

High-power lasers are used to compress a plasma (a gas of charged particles) by radiation pressure. A laser generating radiation pulses with peak power 1900 MW is focused onto 1.2 mm2 of high-electron-density plasma. Find the pressure exerted on the plasma if the plasma reflects all the light beams directly back along their paths. Number i 1.2E5 * Units N/m^2 or Pa

X-rays of wavelength 0.0628 nm are scattered from a crystal with a grazing angle of 11.3°. Assume m = 1 for this process. Calculate the spacing between the crystal planes. d = nm