Explore topic-wise InterviewSolutions in Current Affairs.

This section includes 7 InterviewSolutions, each offering curated multiple-choice questions to sharpen your Current Affairs knowledge and support exam preparation. Choose a topic below to get started.

1.

A plane loop is shaped in the form as shown in figure with radii a=20 cm and b=10 cm and is placed in a uniform time varying magnetic field B=B0 sinω t , where B0=10 mT and ω=100rad/s. Find the amplitude of the current induced(in A) in the loop, if its resistance per unit length is equal to 50×10−3Ωm. The inductance of the loop is negligible.

Answer»

A plane loop is shaped in the form as shown in figure with radii a=20 cm and b=10 cm and is placed in a uniform time varying magnetic field B=B0 sinω t , where B0=10 mT and ω=100rad/s. Find the amplitude of the current induced(in A) in the loop, if its resistance per unit length is equal to 50×103Ωm. The inductance of the loop is negligible.
2.

The radius of a well is 7 m. water init is at a depth of 20m and depth of water column is 10 m.work done in pumping out water completely from the well is,(g=10m/s2)?

Answer»

The radius of a well is 7 m. water init is at a depth of 20m and depth of water column is 10 m.work done in pumping out water completely from the well is,(g=10m/s2)?

3.

An ideal massless spring can be compressed 1 m by a force of 100 N. This same spring is placed at the bottom of a frictionless inclined plane which makes an angle θ=30∘ with the horizontal. A 10 kg mass is released from rest at the top of the incline and is brought to rest momentarily after compressing the spring 2 meters. (a) Through what distance does the mass slide before coming to rest? (b) What is the speed of the mass just before it reaches the spring?

Answer»
An ideal massless spring can be compressed 1 m by a force of 100 N. This same spring is placed at the bottom of a frictionless inclined plane which makes an angle
θ=30 with the horizontal. A 10 kg mass is released from rest at the top of the incline and is brought to rest momentarily after compressing the spring 2 meters.
(a) Through what distance does the mass slide before coming to rest?
(b) What is the speed of the mass just before it reaches the spring?
4.

A ball is projected with momentum 'p' at angle θ from horizontal. What is the change in momentum till it reaches the highest point?

Answer» A ball is projected with momentum 'p' at angle θ from horizontal. What is the change in momentum till it reaches the highest point?
5.

A machine gun fires A bullet of mass 40 gram with the velocity of 1200m/s. The gun can exert a maximum force of 144N on the bullet. How many bullets can it fire per second at the most?

Answer»

A machine gun fires A bullet of mass 40 gram with the velocity of 1200m/s. The gun can exert a maximum force of 144N on the bullet. How many bullets can it fire per second at the most?

6.

A ball moving with velocity i collides with a stationary wall and returns with a velocity i/2. Thecoefficient of restitution for this collision is 1/K. Find the value of K.

Answer» A ball moving with velocity i collides with a stationary wall and returns with a velocity i/2. Thecoefficient of restitution for this collision is 1/K. Find the value of K.
7.

The light from a torch is normally incident on the surface at intensity of illumination I1. If the surface is tilted to 45∘ from initial position, then what will be intensity of illumination I2 on the surface in terms of I1 ?

Answer»

The light from a torch is normally incident on the surface at intensity of illumination I1. If the surface is tilted to 45 from initial position, then what will be intensity of illumination I2 on the surface in terms of I1 ?

8.

A long solenoid of 50 cm length having 100 turns carries a current of 2.5 A. The magnetic induction at the center of the solenoid is [μ0=4π×10−7 T Am−1]

Answer»

A long solenoid of 50 cm length having 100 turns carries a current of 2.5 A. The magnetic induction at the center of the solenoid is [μ0=4π×107 T Am1]

9.

Find x if P is a null point.

Answer»

Find x if P is a null point.




10.

Electrons can remain in an orbit as long as they absorb radiation of definite energy. Is this statement true or false?

Answer» Electrons can remain in an orbit as long as they absorb radiation of definite energy. Is this statement true or false?
11.

Standing waves are produced by the superposition of two waves, y1=0.05sin(3πt−2x) and y2=0.05sin(3πt+2x), where x and y are expressed in metres and t is in seconds. What is the amplitude of a particle at x=0.5 m? Given cos57.3∘=0.54.

Answer»

Standing waves are produced by the superposition of two waves, y1=0.05sin(3πt2x) and y2=0.05sin(3πt+2x), where x and y are expressed in metres and t is in seconds. What is the amplitude of a particle at x=0.5 m? Given cos57.3=0.54.

12.

The graph of y=ln(x2+1) is

Answer»

The graph of y=ln(x2+1) is

13.

The magnitude of electric field intensity E is such that an electron placed in it would experience an electrical force equal to its weight is given by(Mass of e–=m)

Answer»

The magnitude of electric field intensity E is such that an electron placed in it would experience an electrical force equal to its weight is given by

(Mass of e=m)


14.

If an electron and a proton having same momentum enter perpendicular to a magnetic field, then

Answer»

If an electron and a proton having same momentum enter perpendicular to a magnetic field, then


15.

5. A particle is thrown vertically upward from the ground such that,it passes through the same point at t=4s and t=9s.Find height of the point from the ground.[Take g=10m/s2]

Answer» 5. A particle is thrown vertically upward from the ground such that,it passes through the same point at t=4s and t=9s.Find height of the point from the ground.[Take g=10m/s2]
16.

The figure shows a square loop of side 5 cm being moved towards the right at a constant speed of v=1 cm/s. The front edge just enters the 20 cm wide magnetic field at t=0. Find the induced emf in the loop at t=2 s.

Answer»

The figure shows a square loop of side 5 cm being moved towards the right at a constant speed of v=1 cm/s. The front edge just enters the 20 cm wide magnetic field at t=0. Find the induced emf in the loop at t=2 s.


17.

which type of convex lens are used in magnifying glasses?

Answer» which type of convex lens are used in magnifying glasses?
18.

A particle is executing shm about y=0 along y axis .it's position at an instant is given by y=5(sin3πt+√3cos3πt).the amplitude of oscillation is

Answer» A particle is executing shm about y=0 along y axis .it's position at an instant is given by y=5(sin3πt+√3cos3πt).the amplitude of oscillation is
19.

The cylindrical tube of a spray pumphas radius R one end of which has n fine holes each of radius r if speed of the liquid in the tube is V the speed of the ejection of the liquid through the holes is

Answer» The cylindrical tube of a spray pumphas radius R one end of which has n fine holes each of radius r if speed of the liquid in the tube is V the speed of the ejection of the liquid through the holes is
20.

A TV transmission tower has a height of 140 m and the height of the receiving antenna is 40 m. What is the maximum distance upto which signals can be broadcasted from this tower in LOS (Line of Sight) mode? (Given : radius of earth =6.4×106 m).

Answer»

A TV transmission tower has a height of 140 m and the height of the receiving antenna is 40 m. What is the maximum distance upto which signals can be broadcasted from this tower in LOS (Line of Sight) mode? (Given : radius of earth =6.4×106 m).

21.

A chain is placed on a frictionless table with one fourth of it hanging over the edge. If the length of the chain is 2m and its mass is 4kg, the energy need to be spent to pull it back to the table is

Answer»

A chain is placed on a frictionless table with one fourth of it hanging over the edge. If the length of the chain is 2m and its mass is 4kg, the energy need to be spent to pull it back to the table is


22.

How much should the pressure be increased inorder to decrease the volume of a gas by 5% at aconstant temperature?

Answer» How much should the pressure be increased inorder to decrease the volume of a gas by 5% at aconstant temperature?
23.

A continuous time signal x(t) is obtained at the output of an ideal low pass filter with cut off frequency ωc=1000π. If instantaneous sampling is performed on x(t). Which of the following sampling periods will guarantee that x(t) can be recovered properly from its sampled version using an appropriate low-pass filters?

Answer»

A continuous time signal x(t) is obtained at the output of an ideal low pass filter with cut off frequency ωc=1000π. If instantaneous sampling is performed on x(t). Which of the following sampling periods will guarantee that x(t) can be recovered properly from its sampled version using an appropriate low-pass filters?

24.

Half life of a radioactive element is 5 min. and 10 sec. The time taken for 90% of it to disintegrate is nearly,(Given: log102=0.301)

Answer»

Half life of a radioactive element is 5 min. and 10 sec. The time taken for 90% of it to disintegrate is nearly,

(Given: log102=0.301)

25.

A square plate of 1 m side moves parallel to a second plate with velocity 4 m/s. A thin layer of water exist between plates. If the viscous force is 2 N and the coefficient of viscosity is 0.01 Poise, then find the distance between the plates.

Answer»

A square plate of 1 m side moves parallel to a second plate with velocity 4 m/s. A thin layer of water exist between plates. If the viscous force is 2 N and the coefficient of viscosity is 0.01 Poise, then find the distance between the plates.

26.

15.a point charge q moves with a speed v in a circular path of radius r around a long uniformly charged conductor of linear charge densityλ .The speed varies with r as 1) V\propto r^° 2)v\propto r 3)v\propto1/r 4)v\propto1/\sqrt{}r

Answer» 15.a point charge q moves with a speed v in a circular path of radius r around a long uniformly charged conductor of linear charge densityλ .The speed varies with r as 1) V\propto r^° 2)v\propto r 3)v\propto1/r 4)v\propto1/\sqrt{}r
27.

A compound microscope consists of an objective of focal length 1 cm and an eyepiece of focal length 5 cm. An object is placed at a distance of 0.5 cm from the objective. What should be the separation between the lenses so that the microscope projects an inverted real image of the object on a screen 30 cm behind the eyepiece?

Answer»

A compound microscope consists of an objective of focal length 1 cm and an eyepiece of focal length 5 cm. An object is placed at a distance of 0.5 cm from the objective. What should be the separation between the lenses so that the microscope projects an inverted real image of the object on a screen 30 cm behind the eyepiece?

28.

Mass of a man is M and that of disc is M. Disc has radius R. A man walks along circumference of the disc by θ with respect to disc then angular displacement of disc in the same time is θ_1. If it is pivoted at the centre, then θ_1 is (1)θ (2)θ/3 (3) θ/9 (4) 2θ/3

Answer» Mass of a man is M and that of disc is M. Disc has radius R. A man walks along circumference of the disc by θ with respect to disc then angular displacement of disc in the same time is θ_1. If it is pivoted at the centre, then θ_1 is (1)θ (2)θ/3 (3) θ/9 (4) 2θ/3
29.

In YDSE experiment a glass plate of refractive index 1.5 is placed infront of one of the slits. Minimum thickness 't' of this glass plate so that intensity of light at position of central maxima [before glass plate] remains unchanged is

Answer»

In YDSE experiment a glass plate of refractive index 1.5 is placed infront of one of the slits. Minimum thickness 't' of this glass plate so that intensity of light at position of central maxima [before glass plate] remains unchanged is

30.

A car is moving on a straight road. The velocity of the car varies with time as shown in the figure. Initially (at t=0), the car was at x=0, where, x is the position of the car at any time ‘t’. The maximum displacement from the starting position will be

Answer»

A car is moving on a straight road. The velocity of the car varies with time as shown in the figure. Initially (at t=0), the car was at x=0, where, x is the position of the car at any time ‘t’.

The maximum displacement from the starting position will be

31.

If a ray of light is incident on a plane mirror at an angle 60∘ with the mirror surface, then deviation produced by mirror (in degrees) is (Give integer value)

Answer» If a ray of light is incident on a plane mirror at an angle 60 with the mirror surface, then deviation produced by mirror (in degrees) is (Give integer value)


32.

Two pendulums have time period T and 5T/4. They start SHM at the same time from the mean position. What will be the phase difference between them at the moment, when bigger pendulum completes one oscillation?

Answer»

Two pendulums have time period T and 5T/4. They start SHM at the same time from the mean position. What will be the phase difference between them at the moment, when bigger pendulum completes one oscillation?

33.

The change in potential energy when a body of mass m is raised to height nR from the earth's surface is (R is radius of earth)

Answer»

The change in potential energy when a body of mass m is raised to height nR from the earth's surface is (R is radius of earth)

34.

What is the work done by electric force in taking a charged particle of charge 1C by 10 cm along the equator of a dipole?

Answer»

What is the work done by electric force in taking a charged particle of charge 1C by 10 cm along the equator of a dipole?

35.

Electric field intensity at point B due to a point charge Q kept at point A is 24 N/C and the electric potential at point B due to the same charge is 12J/C.Calculate the distance AB and the magnitude of charge Q.

Answer» Electric field intensity at point B due to a point charge Q kept at point A is 24 N/C and the electric potential at point B due to the same charge is 12J/C.Calculate the distance AB and the magnitude of charge Q.
36.

31. How much should be the decrease in pressure to increase the volume of a given mass of a gas by 10%? 1) 9.1% 2) 1.9% 3) 10% 4) 6.5%

Answer» 31. How much should be the decrease in pressure to increase the volume of a given mass of a gas by 10%? 1) 9.1% 2) 1.9% 3) 10% 4) 6.5%
37.

A plane electromagnetic wave, has frequency of 2.0×1010 Hz and its energy density is 1.02×10–8 Jm−3 in vacuum.The amplitude of the magnetic field of the wave is close to:(14πε0=9×109 Nm2C2)and speed of light c=3×108 ms−1

Answer»

A plane electromagnetic wave, has frequency of 2.0×1010 Hz and its energy density is 1.02×108 Jm3 in vacuum.

The amplitude of the magnetic field of the wave is close to:

(14πε0=9×109 Nm2C2)and speed of light c=3×108 ms1


38.

The amplitude of a wave disturbance propagating in the positive x-direction is given by y=11+x2 at t = 0 and y=1[1+(x−1)2] at t = 2s. the wave speed is

Answer»

The amplitude of a wave disturbance propagating in the positive x-direction is given by y=11+x2 at t = 0 and y=1[1+(x1)2] at t = 2s. the wave speed is



39.

In below figure two blocks are placed on fixed inclined plane and friction coefficient between the blocks and inclined plane are μ1 and μ2 respectively as shown in figure. Value of μ1 and μ2 are given in column 1 and value of a1 and a2 are given in column 2 and column 3 respectively. Column 1 Column 2 Column 3(i)μ1=0.8(i)a1=2 m/s2(P)a2=2 m/s2 μ2=0.8 (ii)μ1=0.5(ii)a1=0.8 m/s2(Q)a2=0.8 m/s2 μ2=0.5 (iii)μ1=0.5(ii)a1=4.4 m/s2(R)a2=4.4 m/s2 μ2=0.2 (iv)μ1=0.5(iv)a1=0(S)a2=0 μ2=0.8 In which of the following combination both blocks will move together and normal between them is zero?

Answer»

In below figure two blocks are placed on fixed inclined plane and friction coefficient between the blocks and inclined plane are μ1 and μ2 respectively as shown in figure. Value of μ1 and μ2 are given in column 1 and value of a1 and a2 are given in column 2 and column 3 respectively.

Column 1 Column 2 Column 3(i)μ1=0.8(i)a1=2 m/s2(P)a2=2 m/s2 μ2=0.8 (ii)μ1=0.5(ii)a1=0.8 m/s2(Q)a2=0.8 m/s2 μ2=0.5 (iii)μ1=0.5(ii)a1=4.4 m/s2(R)a2=4.4 m/s2 μ2=0.2 (iv)μ1=0.5(iv)a1=0(S)a2=0 μ2=0.8

In which of the following combination both blocks will move together and normal between them is zero?


40.

The driver of train A moving at a speed of 30 ms^{-1} sights another train B moving on the same track at a speed of 10 ms^{-1} in the same direction. He immediately applies bracks and achieves a uniform retardation of 2 ms^{`-1}. To avoid collision, what must be the minimum dis†an ce between trains A and B when the driver of A sights B?

Answer» The driver of train A moving at a speed of 30 ms^{-1} sights another train B moving on the same track at a speed of 10 ms^{-1} in the same direction. He immediately applies bracks and achieves a uniform retardation of 2 ms^{`-1}. To avoid collision, what must be the minimum dis†an ce between trains A and B when the driver of A sights B?
41.

A prism having an apex angle 4∘ and refractive index 1.5 is located in front of a vertical plane mirror as shown in figure. Through what total angle is the ray deviated after reflection from the mirror?

Answer»

A prism having an apex angle 4 and refractive index 1.5 is located in front of a vertical plane mirror as shown in figure. Through what total angle is the ray deviated after reflection from the mirror?


42.

The magnetic field (B) due to revolving electron at the center is proportional to Z3nx. The value of x is -

Answer»

The magnetic field (B) due to revolving electron at the center is proportional to Z3nx. The value of x is -

43.

A parallel plate capacitor having an area A and separated by a distance d is filled by a copper plate of area A and thickness b. The new capacitance is:

Answer» A parallel plate capacitor having an area A and separated by a distance d is filled by a copper plate of area A and thickness b. The new capacitance is:
44.

A uniform solid sphere of radius R has a cavity of radius 1 m cut from it. If the centre of mass of the system lies at the periphery of the cavity, then:

Answer»

A uniform solid sphere of radius R has a cavity of radius 1 m cut from it. If the centre of mass of the system lies at the periphery of the cavity, then:




45.

A molecule with dipole moment p is placed in an electric field of strength E. Initially the dipole is aligned parallel to the field . If the dipole is to be rotated to be anti-parallel to the field , the work required to be done by an external agency is

Answer»

A molecule with dipole moment p is placed in an electric field of strength E. Initially the dipole is aligned parallel to the field . If the dipole is to be rotated to be anti-parallel to the field , the work required to be done by an external agency is

46.

A circular disc of mass 300 gm and radius 20 cm can rotate freely about a vertical axis passing through is center O. A small insect of mass 100 gm is initially at a point A on the rim. The insect initially stationary starts walking from rest along the rim of disc with such a time varying relative velocity that the disc rotates in the opposite direction with a constant angular acceleration = 2πrad/s2. After some time T, the insect is back at the point A. What is the time taken by insect to reach the original position?

Answer»

A circular disc of mass 300 gm and radius 20 cm can rotate freely about a vertical axis passing through is center O. A small insect of mass 100 gm is initially at a point A on the rim. The insect initially stationary starts walking from rest along the rim of disc with such a time varying relative velocity that the disc rotates in the opposite direction with a constant angular acceleration = 2πrad/s2. After some time T, the insect is back at the point A


. What is the time taken by insect to reach the original position?



47.

A student is standing at a distance of 50 metres from the bus. As soon as the bus starts its motion with an acceleration of 1 m/s2 , the student starts running towards the bus with an uniform velocity u. Assuming the motion to be along a straight road, the minimum value of u, so that the student is able to catch the bus is

Answer»

A student is standing at a distance of 50 metres from the bus. As soon as the bus starts its motion with an acceleration of 1 m/s2 , the student starts running towards the bus with an uniform velocity u. Assuming the motion to be along a straight road, the minimum value of u, so that the student is able to catch the bus is

48.

ntTwo slits in Y.D.S.E are 0.02 cm apart.The interference fringes for light 6000 angstorm are formed on screen 80 cm apart.Find the distance of seventh dark fringe from the centre of the screen.n

Answer» ntTwo slits in Y.D.S.E are 0.02 cm apart.The interference fringes for light 6000 angstorm are formed on screen 80 cm apart.Find the distance of seventh dark fringe from the centre of the screen.n
49.

The electric field at 20cm from the centre of a uniformly charged non conducting sphere of radius 10cm is E then at a distance 5cm from the centre it will be

Answer» The electric field at 20cm from the centre of a uniformly charged non conducting sphere of radius 10cm is E then at a distance 5cm from the centre it will be
50.

An electric stove boils 1 kg of water in time 2 minand another stove boils 1 kg of water in time3 min. Both electric stoves are designed for thesame voltage. When they are joined in parallel, thetime required to boil 1 kg of water is(1) 1.2 min(2) 5 min(3) 2.4 min(4) 1 min

Answer» An electric stove boils 1 kg of water in time 2 minand another stove boils 1 kg of water in time3 min. Both electric stoves are designed for thesame voltage. When they are joined in parallel, thetime required to boil 1 kg of water is(1) 1.2 min(2) 5 min(3) 2.4 min(4) 1 min