Jason takes off from rest across level water on his jet-powered skis. the combined mass of jason and his skis is 75 kg (the mass of the fuel is negligible). the skis have a thrust of 200 n and a coefficient of kinetic friction on water of 0.10. unfortunately, the skis run out of fuel after only 53 s. how far has jason traveled when he finally coasts to a stop?

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?