Two plane parallel conducting plates `1.5xx10^(-2)m` apart are held horizontal one above the other in air. The upper plate is maintained at a positive potential of`1.5kV` while the other plate is earthed. Calculate the number of electrons which must be attached to a small oil drop of mass `4.8xx10^(-15)kg` between the plates of move the drop with constant speed. Neglect the density and viscosity of air.

Two plane parallel conducting plates 1.5xx10^(-2)m apart are help horizontally one aove the other in air. The upper plate is maintained at positive potential of 1.5 kV while the other plate is earthed. Calculate the number of electorns which must be attached to a small oil drop of mass 4.9xx10^(-15)"kg" between the plates to maintain it at rest. If the potential of upper plate is suddenly changed to -1.5 kV, what is the initial acceleration of the charged drop ? Also obtain the terminal velocity of the drop if its radius is 5xx10^(-6)m and coefficient of viscosity of air is 1.8xx10^(-5)N-s//m^(2) . Assuming that the density of air is negligible in comparison with that of oil.

Two horizontal parallel conducting plates are kept at a separation d = 1.5 xx 10^(-2) m apart one above the other in air as shown in figure. The upper plate is maintained at a positive potential of 1.5 kV while the other plate is earthed which maintains it at zero potential. Calculate the number of electrons which must be attached to a small oil drop of mass m =4.9 xx 10^(-15) kg between the plates to maintain it at rest. Consider density of air is negligible in comparison with that ofoil. If the potential of above plate is suddenly changed to -l .5kV , what will be the initial acceleration of the charged drop? Also calculate the terminal velocity of the drop if its radius is r= 5.0 xx 10^(-6)m and the coefficient of viscosity of air is eta = 1.8 x 10--5 N-s//m^(2) [3,2g, 5.7 xx 10^(-5) m//s^(2)]

A charged drop of mass 3.2 xx 10^(-12) g floats between two horizontal parallel plates maintained at potential difference of 980 V and separation between the plates is 2 cm. The number of excess or deficient electrons on the drop is

Two parallel conducting plates , a distance d apart, are held horizontally one above the other in air . Between parallel plates , electric field E is uniform and directed vertically downwards . A spherical ball of radius r , made of a material of density sigma falls with constant velocity v . the coefficient of viscosity of air is eta and density of air is negligible in comparision of sigma . Find electric charge on ball assuming it to be positive.

The Millikan oil-drop experiment enabled the charge on the electron to be deterined. Two parallel metal plates P and Q are situated in a vaccum. The plates are horizontal and separated by a distance of 5.4 mm, as illustrated in fig. The lower plate P is earthed. The potential difference between the plates can be varied. An oil droplet of mass 7.7 xx 10^-15 kg is oserved to remain stationary between the plates , when palte Q is a t a potential of +850 suggest why plates p and Q must be parallel and horizontal and calcualte the charge with its gin, on the oil droplet.

Two parallel conducting plates of area A=2.5m^(2) each are placed 6 mm apart and are both earthed. A third plate, identical with the first two, is placed at a distance of 2 mm from one of the earthed plates and is given a charge of 1 C. The potential of the central plate is

Two parallel conducting plates of area A=2.5m^(2) each are placed 6 mm apart and are both earthed. A third plate, identical with the first two, is placed at a distance of 2 mm from one of the earthed plates and is given a charge of 1 C. The potential of the central plate is

A potential difference of 5000 volt is applied between two parallel plates 5cm apart a small oil drop having a charge of 9.6 xx 10^-19 C falls between the plates. Find (a) electric field intensity between the plates and (b) the force on the oil drop.