Electric potential Flashcards
What is the charge of a proton?
1 e
What is the charge of an alpha particle?
2 e
Define electric potential. Also state if it is an vector/scalar.
Electric potential is the work done in bringing a point charge from infinity to a point in electric field. It is a scalar quantity.
Give electric potential formula.
V=W/Q
What does electric potential depends on? Also what is it independent of?
Electric potential depends on the magnitude of the charge. It is independent of the path taken.
By whom is the work done to bring charge at a point?
The work is done by an external agent.
What is the SI unit of electric potential? Also give the dimensional formula.
The SI unit is Volts. (V), it’s dimensional formula is [M1 L2 T-3 I-1].
Define 1 volt.
If the work done in bringing a charge of +1 C from infinity to a point in the electric field is +1 J, the then the potential is said to be 1 volt.
Define potential difference. Give formula.
Potential difference is the work done in bringing a point charge from one point to other point in the electric field. (Vb-Va)=W (ab)/q
Why is potential difference a conservative force?
As is is path independent.
What happens to potential difference in the direction of electric field?
It decreases.
What is the relation between E and V in uniform electric field? What is the unit of E in this equation?
E=V/L, unit is V/m and also Nm^2C^-1
What is the relation between E and V in non-uniform electric field?
E= - dv/dr
What is potential gradient?
Potential gradient is the rate at which the potential rises with distance.
What is the formula for potential due to a point charge?
V=KQ/r
What is the potential due to a dipole in end-on position?
V=p/4p(E0)[r^2-l^2]
What is the potential due to a dipole in broad side-on position?
V=0
What is the potential due to a dipole in any plane of the dipole surface?
V=Pcos theta/4pi(E0)r^2
Is the work done if we move a charge from one point to another inside a charged sphere?
No, as inside the charged sphere every point has same potential for the fact that a charged sphere is an equipotential surface.
What is the Electric field and electric potential inside a charged shell?
Electric field is = 0 as there is no charge inside the shell, and Electric potential = constant and equal to the value of potential at a surface.
What happens to E and v outside the shell?
They both decreases.
Define equipotential surfaces.
The locus of all the points having same potential is called a equipotential surface.
State all the 5 properties of equipoential surfaces.
1) all points inside it has same potential
2) no to equipotential surfaces intersect
3) the closeness of two equipotential surfaces represents the higher electric field
4) the lines of force are normal to the surface
5) work done to move a charge inside this surface is 0
What is the formula of potential energy?
U=qV
What is the conversion of P.E to K.E
q(Kb-Ka)=Va-Vb
Define electron volt.
The amount of kinetic energy that an electron acquires to accelerate through a potential difference of 1 volt, towards the positive terminal is called electron volt.
How much kinetic energy does a proton gain if it accelerates through a p.d of 1 volt?
1 eV = 1.6*10^-19
What is potential energy of a dipole at [theta=0]?
-PE
What is potential energy of a dipole at [theta=90]?
0
What is potential energy of a dipole at any angle theta?
-PEcostheta
What is the work done in rotating a dipole?
PE[1-costheta]
At what angle is potential energy of a dipole min and max?
min-theta=0
max-theta=180