Physics Model Question Paper 4: (For Class 11 and 12 and Pre-Medical/Engineering Entrance)

Q 1.

A and B are two infinitely long straight parallel conductors. C is another straight conductor of length 1 m kept parallel to A and B as shown in the figure. Then the force experienced by C is

(A) towards B equal to 0.6 ´  10^-5 N

(B) towards A equal to 5.4 ´  10^-5 N

(C) towards B equal to 5.4 ´  10^-5 N

(D) towards A equal to 0.6 ´  10^-5 N

Answer: (A)

Q 2.

A parallel plate capacitor with air as the dielectric has capacitance C. A slab of dielectric constant K and having the same thickness as the separation between the plates is introduced so as to fill one-fourth of the capacitor as shown in the figure. The new capacitance will be

(A)

(B)

(C)

(D)

Answer: (D)

Q 3.

If power dissipated in the 9 W resistor in the circuit shown is 36 Watt, the potential difference across the 2 Wresistor is

(A) 2 Volt

(B) 4 Volt

(C) 8 Volt

(D) 10 Volt

Answer: (D)

Q 4.

In the Wheatstone's network given below, P = 10 W, Q = 20W,  R = 15 W, S = 30W The current passing through the battery (of negligible internal resistance) is

(A) 0.72 A

(B) 0.18 A

(C) 0 A

(D) 0.36 A

Answer: (D)

Q 5.

Symbolic representation of four logic gates are shown as

Pick out which ones are for AND, NAND and NOT gates, respectively:

(A) (ii), (iv) and (iii)

(B) (ii), (iii) and (iv)

(C) (iii), (ii) and (i)

(D) (iii), (ii) and (iv)

Answer: (A)

Q 6.

The current passing through the ideal ammeter in the circuit given below is

(A) 0.5 A

(B) 0.75 A

(C) 1 A

(D) 1.25 A

Answer: (C)

Q 7.

Three long straight wires A, B and C are carrying currents as shown in figure. Then the resultant force on B is directed _______.

(A) towards A.

(B) towards C.

(C) perpendicular to the plane of paper and outward.

(D) perpendicular to the plane of paper and inward.

Answer: (B)

Q 8.

Two identical rods AC and CB made of two different metals having thermal conductivities in the ratio 2 : 3 are kept in contact with each other at the end C as shown in the figure. A is at 100°C and B is at 25°C. Then the junction C is at

(A) 50°C

(B) 75°C

(C) 60°C

(D) 5s°C

Answer: (D)

Q 9.

Which one of the following graphs represents the variation of maximum kinetic energy (E_K) of the emitted electrons with frequency g in photoelectric effect correctly?

(A) 1

(B) 2

(C) 3

(D) 4

Answer: (D)

Q 10.

Effective capacitance between A and B in the figure shown is (all capacitances are in µ F)

(A) 21 µ F

(B) 23 µ F

(C)  µ F

(D)  µ F

Answer: (D)