1. Two identical solid copper spheres of radius r placed in contact with each other. The gravitational attraction is proportional to : ?
2. Why 1.6 multiply 10 to the power -20 coulombs charge is not possible, where as 1.6 multiply 10 to the power -18 coulombs is possible
3. Clock a based on spring oscillations and a clock b based on oscillations of simple pendulum are synchronized on Earth. Both are taken to Mars. Where mass is 0.1 times mass of Earth and Radius is half of Earth's radius. What are the measures of time in both clocks now.
4. A soap solution has bubbles in it. The surface tension of that is S. Radius of a bubble is R and the pressure inside the bubble is atmospheric pressure. What is the electric potential on the surface of bubble?
5. An electric field of 30 n coulomb exists along the negative x axis in space. Calculate the potential difference Vb - Va where the points a and b are given by a=(0,0)and b(0,2)
6. If three infinite charged sheets of uniform surface charge densities of sigma ,2 sigma, - 4 sigma respectively are placed parallel to each other, Find electric field at different points.
7. Two conductors are of uniform shape and size one of them is made of copper, while the other is made of aluminum (less conductive). The charge induced in aluminum will be equal to copper or less or more ?