Four masses are suspended on weithless strings as shown below The tension T1 in the top string is
2 points
T1 = m1+m2+m3+m4
T1 =( m1+m2+m3+m4)g
T1 = m1*g
none of the above
Other:

The tension in the second from top string is *
2 points
T2 =( m1+m2+m3+m4)g
T2 =( m2+m3+m4)g
T2 =( m1+m2)g
T1 =( m1)g

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?