AWES TGT Physics Mock Test - 6 - AWES TGT/PGT MCQ

Lawrence Kohlberg, an American psychologist, has propounded the 'Theory of Moral Development'.

• He has made a systematic study of moral development in his theory that is categorized into 3 levels and 6 stages. 

Radar uses electromagnetic energy pulses. The radio-frequency (rf) energy is transmitted to and reflected from the reflecting object. A small portion of the reflected energy returns to the radar set. This returned energy is called an ECHO. Radar sets use the echo to determine the direction and distance of the reflecting object.
It does not work on phenomena of beats.

Let the velocity of m is v and velocity of 4m is u
Therefore, v = 4u and we know that kinetic energy is 1/2mv² so for m:
KE = ½ x m x v² = 1
And for 4m:
KE = ½ x 4m x 4² = 4
So, ratio of their kinetic energy is 1:4
Hence A

Explanation:

The theory for ideal gases makes the following assumptions

1. Gases consist of particles in constant, random motion. They continue in a straight line until they collide with something—usually each other or the walls of their container.

2. Particles are point masses with no volume. The particles are so small compared to the space between them, that we do not consider their size in ideal gases.

3. No molecular forces are at work. This means that there is no attraction or repulsion between the particles.

4. Gas pressure is due to the molecules colliding with the walls of the container. All of these collisions are perfectly elastic, meaning that there is no change in energy of either the particles or the wall upon collision. No energy is lost or gained from collisions.

5. The time it takes to collide is negligible compared with the time between collisions.

6. The kinetic energy of a gas is a measure of its Kelvin temperature. Individual gas molecules have different speeds, but the temperature and kinetic energy of the gas refer to the average of these speeds.

7. The average kinetic energy of a gas particle is directly proportional to the temperature. An increase in temperature increases the speed in which the gas molecules move.

8. All gases at a given temperature have the same average kinetic energy.

9. Lighter gas molecules move faster than heavier molecules.

Area under F-t curve = change in momentum.

The electrons in a conductor have random velocities and when an electric field is applied, they suffer repeated collisions and in the process move with a small average velocity, opposite to the direction of the field. This is equivalent to positive charge flowing in the direction of the field.

As change of state depends on both temperature and pressure, so, either method A or C can be used. We can understand this by ideal gas equation PV = nRT

The dipole moment is defined as the product of a charge and distance. The dimension of charge (current*time) is [I T] and the dimension of distance is [L]. Therefore the dimension of dipole moment is [L T I]. Its unit in the CGS and the SI system are esu*cm and C*m respectively.

In an RLC circuit, the voltage is always used as a reference and according to the phase of the voltage, the phase of the other parameters is decided.

Potentiometer measures the potential difference using null deflection method, where no current is drawn from the cell; whereas voltmeter needs a small current to show deflection. So, accurate measurement of p.d is done using a potentiometer.

Resultant force is zero, as three forces on the particle can be represented in magnitude and direction by three sides of a       triangle in same order. Hence, by Newton's 2nd law 

Particle velocity  will be same

F =AYΔl/L
Δl = FL/AY

Long distance radio broadcasts use shortwave bands because only these bands can be refracted by the ionosphere.

Parallactic second is the unit of distance because parallactic second is an abbreviation of parsec. Parsec = Parsec is the Unit for larger distances.It is the distance at which a star would make parallax of one Second of arc.

When rubber ball completely filled with water its centre of gravity will be at its centre, as water will fall through hole its COG will shift towards lower side leading to increase in length of pendulum and thus T, when very small amount of water will be left in rubber ball its COG will again shifts upward causing decrease in length and thus T, and finally when rubber ball becomes empty its COG will be at its centre and T will remains same as earlier.

The correct answer is option D
In A,B,C there is a single source (coherent source)while in D there is an interference of thin films whose sources are different ,therefore not coherent.

Constantan is an alloy of copper (55%) and nickel (45%) where Manganin is an alloy of copper (84%) manganese(12%) and nickel (4%).
When all metals show increase in resistivity with increase in temperature and semiconductors show the reverse, Constantan and Manganin show a completely different property.
Their main feature is their low thermal variation of their resistivity, which is constant over a wide range of temperatures.
Metals, including alloys, have free electrons as charge carriers. Their movement controls by defects. One of defects of usual metal is oscillations of atoms due to temperature. More temperature - more oscillations - more collisions of electrons with atoms - less mobility - more resistivity. In alloys, like constantan and Manganin, atoms are in disorder. So they have big resistivity. Their additional disorder due to temperature increase is insignificant. That is why they have no temperature dependence on resistivity.
 

The wires at A and B are perpendicular to the plane of paper and current is towards the reader. Let us consider certain points.
Point C (mid point between A and B) : The magnetic field at C due to A ( ) is in upward direction but magnetic field at C due to B is in downward direction.
Net field is zero.
Point E : Magnetic field due to A is upward and magnetic field due to B is downward but 

∴Net magnetic field is in downward direction.

Net field upwards. Similarly,, other points can be considered.

B because of constructive interference.

The ratio of angular dispersion to the angle of deviation for the mean wavelength is called Dispersive Power. Represented by 

where δ_v − δ_r is the angular dispersion for violet and red lights and δ_r the deviation suffered by the mean light.

Frequency=C/ λ
λ=h/P
frequency=C P/ h
f=(3×10⁸×3.3×10^-29)/6.6×10^-34
f=3× 10¹³/2
f=1.5×10¹³ Hz

Escape velocity is the minimum velocity with which the body has to be projected vertically upwards from the surface of the earth so that it crosses the gravitational field of earth and never returns back on its own.

The minimum force required to start pushing a body up a rough inclined plane is 
F1=mgsinθ+ μgcosθ            ......(i)
Minimum force needed to prevent the body from sliding down the inclined plane is
F2=mgsinθ− μgcosθ           ...........(ii)
Divide (i) by (ii), we get
F1/F2
=sinθ+μcosθ/ sinθ−μcosθ 
= tanθ+μ/tanθ−μ
= 2μ+μ/2μ−μ 
=3              (tanθ=2μ (given))

Mirage is formed by total internal reflection in deserts where due to heating of earth, refraction index of air near the surface of earth becomes lesser than above it.

Momentum is conserved in all types of collision whether it is elastic or inelastic where as kinetic energy is lost in sound energy in the absence of external force in inelastic collision.

I1/I2 = W1/W2 = 100/1 = (a1/a2)²
a1/a2 = 10/1
a1 = 10x
a2 = x
Imax/lmin = (a1+a2/a1-a2)²
(10x+x/10x-x)²
(11x/9x)²
(11/9)²
121/81

Mass of pieces according to the statement-

According to law of conservation of momentum


so v = 25 ms^-1

Maximum speed with which the boy can throw stone is:

Range is maximum when the projectile is thrown at an angle of 45⁰ thus,