2020 NEET NEET Question Paper

2020 NEET NEET Questions

1.

A wire of length L, area of cross section A is hanging from a fixed support. The length of the wire changes to L1 when mass M is suspended from its free end. The expression for Young’s modulus is :

A.

Mg(L1-L) / AL

B.

MgL/AL1

C.

MgL/A(L1-L)

D.

MgL1/AL

ANSWER :

C. MgL/A(L1-L)

2.

A cylinder contains hydrogen gas at pressure of 249 kPa and temperature 27°C.
Its density is : (R = 8.3 J mol–1 K–1)

A.

0.2 kg/m3

B.

0.1 kg/m3

C.

0.02 kg/m3

D.

0.5 kg/m3

ANSWER :

A. 0.2 kg/m3

3.

Light with an average flux of 20 W/cm2 falls on a non-reflecting surface at normal incidence having surface area 20 cm2. The energy received by the surface during time span of 1 minute is :

A.

12 × 103 J

B.

24 × 103 J

C.

48 × 103 J

D.

10 × 103 J

ANSWER :

B. 24 × 103 J

4.

Two bodies of mass 4 kg and 6 kg are tied to the ends of a massless string. The string passes over a pulley which is frictionless (see figure). The acceleration of the system in terms of acceleration due to gravity (g) is :

A.

g/2

B.

g/5

C.

g/10

D.

g

ANSWER :

B. g/5

5.

The mean free path for a gas, with molecular diameter d and number density n can be expressed as :

A.

1/√nπd2

B.

1/√2n2πd2

C.

1/√2n2π2d2

D.

1/√2nπd

ANSWER :

A. 1/√nπd2

6.

A ball is thrown vertically downward with a velocity of 20 m/s from the top of a tower. It hits the ground after some time with a velocity of 80 m/s. The height of the tower is : (g = 10 m/s2)

A.

340 m

B.

320 m

C.

300 m

D.

360 m

ANSWER :

C. 300 m

7.

The color code of a resistance is given below

The values of resistance and tolerance, respectively, are

A.

47 kΩ, 10%

B.

4.7 kΩ, 5%

C.

470 Ω, 5%

D.

470 kΩ, 5%

ANSWER :

C. 470 Ω, 5%

8.

When a uranium isotope 23592U is bombarded with a neutron, it generates 8936Kr, three neutrons and :

A.

9140Zr

B.

10136Kr

C.

10336Kr

D.

14456Ba

ANSWER :

D. 14456Ba

9.

A spherical conductor of radius 10 cm has a charge of 3.2 × 10–7 C distributed uniformly. What is the magnitude of electric field at a point 15 cm from the centre of the sphere?
(1/4π∈0 = 9 × 109 Nm2/C2)

A.

1.28 × 105 N/C

B.

1.28 × 106 N/C

C.

1.28 × 107 N/C

D.

1.28 × 104 N/C

ANSWER :

A. 1.28 × 105 N/C

10.
A ray is incident at an angle of incidence i on one surface of a small angle prism (with angle of prism A) and emerges normally from the opposite surface. If the refractive index of the material of the prism is Ξ, then the angle of incidence is nearly equal to :
A.
2A/Ξ
B.
ΞA
C.
ΞA/2
D.
A/2Ξ
ANSWER :
B. ΞA