Sample AFMC Physics Mock Test - NEET MCQ

A mass defect refers to the difference in mass between of an atom and the sum of the masses of the protons, neutrons, and electrons of the atom. The "missing" mass is the energy released by the formation of the atomic nucleus.

Heavy Water is an excellent moderator due to its high moderating ratio and low absorption cross section for neutrons.

Millikan determined the mass of the electron by measuring the charge of the electron.

R_T=60 ohms @ T=500^oC

Also, R_T′​=20 ohms @ T′=20^oC

Resistance at a given temperature R_T​=R_T′​[1+α(T−T′)]

Let resistance of wire is 25 ohm at temperature T′′.

Photo cell is used to convert photon energy(i.e. light energy) into chemical energy.

The coupled flux of two coils system is used to define the mutual inductance between the coils. The mutual inductance between the coils is 

So it is defined as the proportionality between the emf generated in coil 2 due to the current flows in coil 1. Thus It depends on the relative position and orientation of two coils. 

V = 5cos2πft    [ω = 2πf]

V = 5cosωt

=5sin(ωt+π2)  and i = 2sinωt

Power = Vrms×irms×cosφ=0

(Since φ = π/2, therefore cosφ = cos(π/2)=0)

As current is increasing, induced e.m.f. is in opposite direction, therefore, e = - 1 mV.

The capacitance is proportional to the surface area of the conducting plate and inversely proportional to the distance between the plates. Hence, it depends upon the size of the conductor, and not upon the nature of conductor, thickness or colour.

The capacity of a parallel plate condenser is given as,

When the separation between the plates is halved then the new capacity of the condenser is given as,

Thus, the new capacity of parallel plate condenser is 2C.

Time period is not dependent on radius.

Using Gauss's law for electrostatics,

Electric field at charged particle would be given as,

So centripetal force on particle is, 

When the vapour is injected into the evacuated vessel, the pressure of the vessel starts to increase. As the pressure is increased and reaches the saturated vapour pressure, the vapour starts to condense beyond this. Therefore, after a particular instant, the pressure of the container becomes constant.

So, the pressure increases initially and then becomes constant.

Change in momentum (P)=2mv cosθ

P=2mv cos 30°

 P=2mv√3/2 

P=√3mv

If the current flows on the surface of a long hollow copper pipe. Then the magnetic field inside is zero. Hence, there shall be magnetic field produced outside the pipe.

• Height of capillary rise liquid is given by h = 2T/(rρg) . T is surface tension, r is radius of capillary tube, ρ is density and g is acceleration due to gravity.
• Since acceleration due to gravity is in denominator and acceleration due to gravity is negligibly small at the orbit where satteleite is revolving around the earth, capillary rise will be very high.
• So 'full length' may be the correct answer.

Apparent weight in air

Pressure × Radius = Surface Tension
Here the pressure is Gauge Pressure, i.e the difference between absolute pressure and atmospheric pressure 
Hence ratio of gauge pressures is 1:2 
Accordingly ratio of radii is 2:1 
Since Volume∝radius³ 
Hence ratio of volumes is 8:1

ATQ, equation of continuity,

Area is inversely proportional to flow rate, 

therefore if area is reduced by four times 

the flow rate becomes 4 times = 4v

• When the surface area of  the liquid is increased molecules from the interior of the liquid rise to surface.
• As these molecules reach the surface work is done against the cohesive force.This work is stored in the molecules in the form of potential energy.
• Thus, the  potential energy of the molecules lying in the surface is greater than that of the molecules in the interior of the liquid.

If the angle of contact is less than 90 ,then the level of water rises in concave meniscus.

• Elasticity depends on temperature.
• Also, elasticity changes due to impurities because they increase binding of crystal grains., hence enhancing elasticity.
• Hammering also changes the structure of material as crystal grains break up into smaller units which plays a large role in determining elasticity (increases elasticity).
• Also, annealing tends to form a uniform orientation of crystal grains, hence producing larger crystal and changing elasticity.

We know that, E = -dΦ/dt,
E = -d/dt {2t² - 3t + 1}
= -(4t - 3)
at t = 0.25 sec,...
E = -(4×0.25 - 3) = 2 V

From the above relation we can see that magnification is directly proportional to the focal length of objective lens.