A proton with the mass m is projected into a uniform electric field that points vertically upward and has magnitude E. The initial velocity of the proton has a magnitude vo and is directed at an angle a below the horizontal.

23d) only typing Solve this question, without any mistakes

Ch 18 q3 In 1910 Rutherford performed a classic experiment in which he directed a beam of alpha particles at a thin gold foil. He unexpectedly observed a few of the particles scattered almost directly backward. This result was not consistent with then current models of atomic structure and led Rutherford to propose the existence of a very dense concentration of positive charge at the center of an atom—the atomic nucleus. The alpha particle has a charge of +2e and the gold nucleus a charge of +79e. Suppose that an alpha particle is initially a great distance from the gold, has a kinetic energy of 4.20 MeV (4.20  106 eV), and is headed directly at a gold nucleus. How close will the particle come to the center of the nucleus? Treat the nucleus and the alpha particle as point charges.

5. In below figure, a small, non-conductor ball of mass m =3.0 mg and charge q = 9.0 µC hangs from an insulating thread that makes an angle e charged non- conductor plane. Considering the gravitational force on the ball and assuming the plane extends far vertically and into and out of the page, calculate the area charge density of the plane. Length of string is 120.0 cm. 30° with a vertical, uniformly lo120cm + Jplone