Because the plate is conductor and the conductor placed in electric field polarizes, i.e. one side of the plate electrifies positive and the other side negative. Also, the electric field inside a conductor is equal zero.
Homework Statement
Uncharged metal plate area S and thickness d located at a distance r from the point charge q and oriented perpendicular to the vector r, as shown below. Find the electric force between the plate and the charge.
The plate thickness is less, and the distance r is much greater...
Let's say I choose an axis going through the second proton which is fixed. Vector of electrical force creating external forces momentum goes through the axis, so the momentum of external forces equals zero. Then the initial and final angular moments would be:
L_i = mvr
L_f = mv_1x
L_i =...
Homework Statement
A proton is moving at speed v from infinity toward a second stationary proton, as shown below. Determine the minimal distance between them.
http://s27.postimg.org/lmw3d21j7/Untitled.png Homework Equations
W = \frac{kq_1q_2}{r}
E_k = \frac{mv^2}{2}
The Attempt at a...