Two astronauts throw an apple/orange at each other. The apple has ma=0.13kg and va=1.11m/s. The orange has mo=0.16kg and vo=-1.21m/s. The fruits collide elastically and the orange then has vo=1.16m/s at θ=42o with respect to its original direction. What’s the final speed/direction of the apple relative to its initial direction?

Cyclotrons are widely used in nuclear medicine for producing short-lived radioactive isotopes. these cyclotrons typically accelerate h- (the hydride ion, which has one proton and two electrons) to an energy of 5 mev to 20 mev. this ion has a mass very close to that of a proton because the electron mass is negligible—about 1 2000 of the proton’s mass. a typical magnetic field in such cyclotrons is 1.9 t. (a) what is the speed of a 5.0-mev h-? (b) if the h- has energy 5.0 mev and b = 1.9 t, what is the radius of this ion’s circular orbit?