Q 12.1: Compare magnitudes of electrical and gravitational force exerted on an object (mass 20 g charge = 20 micro C) by an identical object that is placed 10 cm from the first. (G = 6.67 * 10(-11) Nm(2)kg(-2))

12.2 Calculate the net electrostatic force on q as shown in the figure.

Q 12.3 A point charge q = -8 * 10(-8) C is placed at the origin. Calculate electric field at a point 2 m from the origin on the z axis?

Q 12.4 Determine the electric field at the position r = (4i + 3j) m caused by as point charge q = 5 * 10(-6) placed at origin.

Q 12.5 Two point charges, q1 = -1 * 10(-6) C and q2 = 4 * 10(-6) C, separated by a distance of 3 m. Find and justify the zero field location.

Q 12.6 Find the electric field strength required to hold suspended particle of mass 1 * 10(-6) kg and charge 1 micro C between two plates 10 cm apart.

Q 12.7 A particle having a charge of 20 electrons on it falls through a potential difference of 100 volts. Calculate the energy acquired by it in electron volts (eV).

Q 12.8 In Millikan’s experiment, oil droplets are introduced into the space between two flat horizontal plates, 500 mm apart. The plate voltage is adjusted to exactly 780 Volts so that the droplet is held stationary. The plate voltage is switched off and the selected droplet is observed to fall a measured distance of 1.50 …

Q 12.9 A proton placed in uniform electric field of 5000 NC(-1) directed to right is allowed to go a distance of 10 cm from A to B. Calculate: (a) Potential difference between the two points (b) Work done (c) The change in Potential Energy of the proton (d) The change in Kinetic Energy of …

Q 12.10 Using zero reference point at infinity, determine the amount by which a point charge of 4 * 10(-8) C alters the electric potential at point 1.2m away, when (a) charge is positive (b) charge is negative