Q. As observed from Earth, the wavelength of Hβ in the spectrum of the star Megrez in the Big Dipper is 486.112 nm. Laboratory measurements demonstrate that the normal wavelength of this spectral line is 486.133 nm. Is the star coming toward us or moving away from us? At what speed?
Q. A bicyclist of mass 61 kg (including the bicycle) can coast down a 6.00 degree hill at a steady speed of 8 km/h because of air resistance. How much force should be applied to climb the hill at the same speed and same air resistance?