## An electron is taken from point A to point B along the path AB in a uniform electric field of intensity E = 10 Vm-1. Side AB = 5m, and side BC = 3m. Then, the amount of work done on the electron by us is

Q. An electron is taken from point A to point B along the path AB in a uniform electric field of intensity E = 10 Vm-1. Side AB = 5m, and side BC = 3m. Then, the amount of work done on the electron by us is (a) 50 eV
(b) 40 eV
(c) 50 eV
(d) 40 eV
Ans: B

## In moving from A to B along an electric field line, the work done by the electric field on an electron is 6.4 ×10-19 J. If φ1 and φ2 are equipotential surfaces, then the potential difference VC  VA is

Q.In moving from A to B along an electric field line, the work done by the electric field on an electron is 6.4 × 10-19 J. If φ1 and φ2  are equipotential surfaces, then the potential difference VC − VA is (a) 4 V
(b) 4 V
(c) zero
(d) 6.4 V
Ans: B

## Two spherical conductors of radii R1 and R2 are separated by a distance much larger than the radius of either sphere. The spheres are connected by a conducting wire as shown in figure. If the charges on the spheres in equilibrium are q1 and q2, respectively, what is the ratio of the field strength at the surfaces of the spheres?

Two spherical conductors of radii R1 and R2 are separated by a distance much larger than the radius of either sphere. The spheres are connected by a conducting wire as shown in figure. If the charges on the spheres in equilibrium are q1 and q2, respectively, what is the ratio of the field strength at the surfaces of the spheres? (a) R2 / R1
(b) R22/R12
(c) R1 / R2
(d) R12/R22
Ans: A

## When a 2 μC charge is carried from point A to point B, the amount of work done by the electric field is 50 μJ. What is the potential difference and which point is at a higher potential?

Q. When a 2 μC charge is carried from point A to point B, the amount of work done by the electric field is 50 μJ. What is the potential difference and which point is at a higher potential ?
(a) 25 V, B
(b) 25 V, A
(c) 20 V, B
(d) both are at same potential
Ans: B

## A large insulates sphere of radius r charged with Q units of electricity is placed in contact with a small insulated uncharged sphere of radius r’ and is then separated. The charge on the smaller sphere will now be

A large insulates sphere of radius r charged with Q units of electricity is placed in contact with a small insulated uncharged sphere of radius r’ and is then separated. The charge on the smaller sphere will now be
(a) (Q(r’+r))/r’
(b) (Q(r’+r))/r
(c) Qr/(r’+r)
(d) Qr’/(r+r)
Ans: D