XII CLASS (2022-23)
UNIT TEST – 2 PHYSICS
SET – A
20 Marks
SET – A
1. A 500 μC charge is at the centre of a square of side 10 cm. Find the work done in moving a charge of
10 μC between two diagonally opposite points on the square. (1M)
2. A point charge Q is placed at point “P” as shown in the figure.
.Q————————-.A——.B
Is the potential difference VA-VB positive, negative or zero, if Q is (i) positive (ii) negative (1 M)
3. Plot a graph showing variation of charge “q” versus potential difference “V” for two capacitors C1 and C2.
Both the capacitors have same plate area but plate separation of C2 is smaller than that of C1. (1M)
4. Two thin concentric shells of radii 2m and 4m have charges 3 C and 6 C. Find the ratio of the potential
at the surface for inner shell and outer shell. (1M)
5. Sketch a graph to show how the capacitance ‘C ‘of a capacitor varies with the charge ’q’ given to it.(1M)
6. Sketch equipotential surface of two equal and opposite charges. (1 M)
7. Two conducting wires X and Y of same diameter but different materials are joined in series across a
battery. If the number density of electrons in X is twice that in Y, find the ratio of electrons in the
two wires. (1 M)
8. Two wires of equal length, one of copper and the other of manganin (alloy) have the same
resistance. Which wire is thicker? (1 M)
9. Apply kirchoff’s laws to derive the balance condition of wheatstone bridge. (2 M)
10. On what factors internal resistance of a cell depends. (any four) (2M)
11.What are ohmic and non-ohmic conductors. Give one example of each. (2 M)
12.State principle of capacitor. Derive the expression for the capacitance of a parallel plate capacitor
having plate area A and plate separation d. (3 M)
13.Define drift velocity and derive the expression for drift velocity. How drift velocity varies with
temperature? (3 M)
SET – B
1. A 400 μC charge is at the centre of a square of side 20 cm. Find the work done in moving a
charge of 20 μC between two diagonally opposite points on the square. (1M)
2. A point charge Q is placed at point “P” as shown in the figure.
.Q————————-.A——.B
Is the potential difference VA-VB positive, negative or zero, if Q is (i) positive (ii) negative (1 M)
3. Plot a graph showing the variation of charge “q” versus potential difference “V” for two capacitors C1 and C2. Both the capacitors have same plate area but plate separation of C2 is smaller than that of C1. (1M)
4. Two thin concentric shells of radii 1m and 3m have charges 2 C and 8 C. Find the ratio of the potential
at the surface for inner shell and outer shell. (1M)
5. Sketch a graph to show how the capacitance C of a capacitor varies with the charge ’q’ given to it. (1M)
6. Sketch equipotential surface of two equal positive charges. (1 M)
7. Two conducting wires X and Y of same diameter but different materials are joined in series across a
battery. If the number density of electrons in X is half of that in Y, find the ratio of electrons in the
two wires. (1 M)
8. Two wires of equal length, one of copper and the other of manganin (alloy) have the same
resistance. Which wire is thicker? (1 M)
9. Apply kirchoff’s laws to derive the balance condition of wheatstone bridge. (2 M)
10. On what factors internal resistance of a cell depends. (any four) (2M)
11. What are ohmic and non-ohmic conductors. Give one example of each. (2 M)
12.State principle of capacitor. Derive the expression for the capacitance of a parallel plate capacitor
having plate area A and plate separation d. (3 M)
13.Define drift velocity and derive the expression for drift velocity. How drift velocity varies with
temperature?