Q1. A proton flies with an initial velocity v_o into a parallel plate capacitor in a direction making an angle  to the nagative plate and leaves the capacitor at an angle  to the plates. The length of the capacitor plates is L. Find the intensity E of the field between the plates and the kinetic energy of the electron as it leaves the capacitor. take the mass and charge of the proton as m and e respectively.

 

Q2. Two spherical bobs of same mass and radius having equal charges are suspened from the same point by string of same length. The bobs are immersed in a liquid of dielectric constant K and density _o . Find the density  of the bob for which the angle of divergence of the strings to be the same in the air and in the liquid.