Find the fraction of 7.7-MeV α particles that is deflected at an angle of 90° or more from a gold foil of 10 -6 m thickness.

Problem 9: Rutherford Scattering A gold foil (5.9×1022 atoms/cm³) of "hair" thickness 80 µm is used in a Rutherford experiment to scatter a particles with energy 5 MeV. Find the fraction of particles scattered at angles 0 > 30°.

The speed of the alpha particles in Rutherford experiment was 0.01c, the scattering material was gold. What was the impact parameter of the alpha particle scattered by 60°?

In the Millikan oil drop experiment tiny charged oil droplets generated by a spray are allowed to fall under gravity through a hole in a top electrode, T, towards a bottom electrode B separated from T by 1 cm. When a holding voltage Vh = +0.25V is applied between T and B the droplets are seen to be suspended motionless between the electrodes. What is the specific charge of the droplet q/m? Select one: a. 2.7 C/kg b. 1.5 C/kg c. 0.16 C/kg d. 0.392 C/kg

The threshold frequency of a polished metal surafce is 8.80 x1014Hz. The work function of the surface is? _eV