Q- What is the angle between the direction of electric field at I ) axial line ii ) equatorial line due to an electric dipole ? (1)

Q Explain how electron mobility for a conductor changes when the temperature is decreased at constant potential difference ? (1)

Q Write two special characteristics of manganin due to which it is used for making standard resistance. (1)

Q- The electric potential as a function of distance is as shown below .Construct the graph of electric field vs. distance (2)

Q- Calculate the temperature at which the resistance of a conductor becomes 20% more than its resistance at 22 ⁰ C ( a = 2 *10 ^-4 / K-) (2)

Q A cell of e.m.f. E and internal resistance r is connected to a variable resistance R. Plot the graph to show the variation of I )e.m.f. with R ii )potential difference with R (2)

Q- Two identical parallel metallic plates separated at distance of 0.1 cm. As shown in fig. Surface A is given appositive potential of 10V and B is earthed. I )What is the magnitude and the direction of electric field between points and Y and Z ? ii )What is the work done in moving a charge of 20mC from X to Y ? (2)

Q. Use Gauss”s law to obtain an expression for the electric field due to an infinitely long straight uniformly charge wire? (2)

Q- An electric dipole of dipole moment p is placed in uniform electric field E. Write the expression for torque .Identify two pairs of perpendicular vector in the expression. Show diagrammatically the orientation of the dipole in the field for which the torque is I )maximum ii )half the maximum value ? (3)

Q Calculate the current drawn from the battery \(3)

Q. The given figure shows the experimental set up of the meter bridge. The null point is found to the 60 cm away form the end A with X and Y in position as shown. When a resistance of 15W is connected in series with Y, the null point shift by 10 cm towards the end A of the wire. Find the postion of null point if a resistance of 30W were connected in parallel with Y.(3)

Q. (i) Why is a potentio meter preferred over the volt meter for determining the emf of the cell.

(ii) Two students X and Y perform an experiment on potentio meter separately using the circuit the diagram shown here.: Keeping other things unchanged,

(i) X increase the value of resistance R (ii) Y decreases the value of resistance S in the set up. How would these changes affect the position of null point in each case and why? (3)

Q (i) Obtain an expression for the capacitance of a parallel plate capacitor

(ii) Calculate the total charge an energy stored in a following network. (5)