Practice problems on NEET, NEET 2013

Question 1

In an experiment four quantities a,b,c and d  are measured with percentage error 1%,2%,3%  and 4%  respectively. Quantity P is calculated as follows:P=cda3b2​ %  error in  P is:

Accepted Answer

14%

Answer

10%

Answer

7%

Answer

4%

Question 2

The velocity of a projectile at the initial point A is (2i^+3j^​)m/s . I's velocity (  in m/s)  at point B is :

Accepted Answer

2i^−3j^​

Answer

−2i^−3j^​

Answer

−2i^+3j^​

Answer

2i^+3j^​

Question 3

Aston falls freely under gravity. It covers distances h1​,h2​  and h3​ in the first 5 seconds, the next 5 seconds and the next 5 seconds respectively. The relation between h1​,h2​  and h3​  is:

Accepted Answer

h1​=3h2​​=5h3​​

Answer

h1​=2h2​=3h3​

Answer

h2​=3h1​  and h3​=3h2​

Answer

h1​=h2​=h3​

Question 4

Three blocks with masses m,2m  and 3m  are connected by strings, as shown in the figure. After an upward force F  is applied on block m , the masses move upward at constant speed v.  What is the net force on the block of mass 2m  ?(g is the acceleration due to gravity)

Accepted Answer

Zero

Answer

2mg

Answer

3mg

Answer

6mg

Question 5

The upper half of an inclined plane of inclination θ  is perfectly smooth while lower half is rough. A block starting from rest at the top of the plane will again come to rest at the bottom, if the coefficient of friction between the block and lower half of the plane is given by:

Accepted Answer

μ=2tanθ

Answer

μ=tanθ1​

Answer

μ=tanθ2​

Answer

μ=tanθ

Question 6

A uniform force of (3i^+j^​)  newton acts on a particle of mass 2 kg . Hence the particle is displaced from position (2i^+k^)  meter to position (4i^+3j^​−k^)  meter. The work done by the force on the particle is:

Accepted Answer

9 J

Answer

6 J

Answer

13 J

Answer

15 J

Question 7

An explosion breaks a rock into three parts in a horizontal plane. Two of them go off at right angles to each other. The first part of mass 1 kg  moves with a speed of 12 ms−1  and the second part of mass 2 kg  moves with 8 ms−1  speed. If the third part flies off with 4 ms−1  speed, then its mass is:

Accepted Answer

5 kg

Answer

3 kg

Answer

7 kg

Answer

17 kg

Question 8

A rod PQ  of mass M and length L is hinged at end P. The rod is kept horizontal by a massless string tied to point Q as shown in figure. When string is cut, the initial angular acceleration of the rod is:

Accepted Answer

2L3g​

Answer

g/L

Answer

2g/L

Answer

3 L2 g​

Question 9

A small object of uniform density rolls up a curved surface with an initial velocity ′v′ . It reaches upto a maximum height of 4g3v2​  with respect to the initial position. The object is :

Accepted Answer

Disc

Answer

Ring

Answer

Solid sphere

Answer

Hollow sphere

Question 10

A body of mass ' m  ' is taken from the earth's surface to the height equal to twice the radius (R)  of the earth, The change in potential energy of body will be:

Accepted Answer

32​mgR

Answer

mg2R

Answer

3mgR

Answer

31​mgR

Question 11

Infinite number of bodies, each of mass 2 kg  are situated on x -axis at distances 1 m,2 m,4 m , 8 m,…….  respectively, from the origin. The resulting gravitational potential due to this system at the origin will be:

Accepted Answer

−4G

Answer

−G

Answer

−38​G

Answer

−34​G

Question 12

The following four wires are made of the same material. Which of these will have the largest extension when the same tension is applied?

Accepted Answer

Length =50 cm , diameter =0.5 mm

Answer

Length =100 cm , diameter =1 mm

Answer

Length =200 cm , diameter =2 mm

Answer

Length =300 cm , diameter =3 mm

Question 13

The wettability of a surface by a liquid depends primarily on:

Accepted Answer

Angle of contact between the surface and the liquid

Answer

Viscosity

Answer

Surface tension

Answer

Density

Question 14

The molar specific heats of an ideal gas at constant pressure and volume are denoted by Cp​  and Cv​ , respectively. If γ=Cv​Cp​​  and R is the universal gas constant, then Cv​  is equal to:

Accepted Answer

(γ−1)R​

Answer

1−γ1+γ​

Answer

R(γ−1)​

Answer

γR

Question 15

A piece of iron is heated in a flame. It first becomes dull red then becomes reddish yellow and finally turns to white hot. The correct explanation for the above observation is possible by using:

Accepted Answer

Wien's displacement Law

Answer

Stefan's Law

Answer

Kirchoff's Law

Answer

Newton's Law of cooling

Question 16

A gas is taken through the cycle A→B,B→C,C→A , as shown. What is the net work done by the gas?

Accepted Answer

1000 J

Answer

2000j

Answer

Zero

Answer

−2000 J

Question 17

During an adiabatic process, the pressure of a gas is found to be proportional to the cube of its temperature. The ratio of Cv​CP​​  for the gas is:

Accepted Answer

23​

Answer

34​

Answer

2

Answer

35​

Question 18

In the given (V−T)  diagram, what is the relation between pressures P1​  and P2​  ?

Accepted Answer

P2​<P1​

Answer

P2​=P1​

Answer

P2​>P1​

Answer

Cannot be predicted

Question 19

The amount of heat energy required to raise the temperature of 1 g  of Helium at NTP , from T1​K  to T2​ K  is:

Accepted Answer

83​Na​kB​(T2​−T1​)

Answer

23​ Na​kB​(T2​−T1​)

Answer

43​Na​kB​(T2​−T1​)

Answer

43​ Na​kB​( T1​T2​​)

Question 20

A wave travelling in the + Ve x -direction having displacement along y -direction as 1 m , wavelength 2πm  and frequency of π1​Hz  is represented by:

Accepted Answer

y=sin(x−2t)

Answer

y=sin(2πx−2πt)

Answer

y=sin(10πx−20πt)

Answer

y=sin(2πx+2πt)