13232 + Interview Questions in Physics Page 21 InterviewSolution

1001.	A ball is dropped from a height of 10 m. If the energy of the ball reduces by 40% after striking the ground, how much high can the ball bounce back (in meters)? (Take g = 10 ms2)
Answer» A ball is dropped from a height of 10 m. If the energy of the ball reduces by 40% after striking the ground, how much high can the ball bounce back (in meters)? (Take g = 10 $\frac{m}{s^{2}}$ )

Discussion

1002.	What are the characteristics of image formed by concave lens?
Answer» What are the characteristics of image formed by concave lens?

Discussion

1003.	For the given object (O) and mirror arrangement, the velocity of the image with respect to ground will be [All the velocities are given with respect to ground]
Answer» For the given object (O) and mirror arrangement, the velocity of the image with respect to ground will be [All the velocities are given with respect to ground]

Discussion

1004.	The international space station is maintained in a nearly circular orbit with a mean altitude of 330 km and a maximum of 410 km. An astronaut is floating in the space station’s cabin. The acceleration of astronaut as measured from the earth is.
Answer» The international space station is maintained in a nearly circular orbit with a mean altitude of 330 km and a maximum of 410 km. An astronaut is floating in the space station’s cabin. The acceleration of astronaut as measured from the earth is.

Discussion

1005.	36.What is the path followed by a moving body, on which a constant force acts in a direction other than initial velocity(i.e. excluding parallel and antiparallel direction)? (1) Straight line (2) Parabolic (3) Circular (4) Elliptical
Answer» 36.What is the path followed by a moving body, on which a constant force acts in a direction other than initial velocity(i.e. excluding parallel and antiparallel direction)? (1) Straight line (2) Parabolic (3) Circular (4) Elliptical

Discussion

1006.	A Quantity which has both magnitude and direction is called.
Answer» A Quantity which has both magnitude and direction is called.

Discussion

1007.	In the experiment to study the variation in square of time period of simple pendulum with its length:
Answer» In the experiment to study the variation in square of time period of simple pendulum with its length:

Discussion

1008.	A capacitor of capacitance C, is connected across an AC source of voltage V, given by V=V0sinωt. The displacement current between the plates of the capacitor, would then be given by
Answer» A capacitor of capacitance $C,$ is connected across an AC source of voltage $V,$ given by $V = V_{0} sin ω t$ . The displacement current between the plates of the capacitor, would then be given by

Discussion

1009.	A hoop and a solid cylinder of same mass and radius are made of a permanent magnetic material with their magnetic moments parallel to their respective axes. But the magnetic moment of hoop is twice that of solid cylinder. They are then placed in a uniform magnetic field in such a manner that their magnetic moments make a small angle with the field. If the oscillation periods of hoop and cylinder are Th and Tc respectively, then
Answer» A hoop and a solid cylinder of same mass and radius are made of a permanent magnetic material with their magnetic moments parallel to their respective axes. But the magnetic moment of hoop is twice that of solid cylinder. They are then placed in a uniform magnetic field in such a manner that their magnetic moments make a small angle with the field. If the oscillation periods of hoop and cylinder are $T_{h} a n d T_{c}$ respectively, then

Discussion

1010.	Can a magnet be used to magnetize a piece of iron? How?
Answer» Can a magnet be used to magnetize a piece of iron? How?

Discussion

1011.	Draw the displacement-time graph for the values given below. Displacement after 1 s,2 s,3 s and 4 s are 5 m,10 m,15 m and 20 m respectively. [2 MARKS]
Answer» Draw the displacement-time graph for the values given below. Displacement after $1 s, 2 s, 3 s a n d 4 s$ are $5 m, 10 m, 15 m a n d 20 m$ respectively. [2 MARKS]

Discussion

1012.	Find out the appropriate word which fits the 1st blank.
Answer» Find out the appropriate word which fits the 1st blank.

Discussion

1013.	19.When a current of 0.2A is drawn from a battery ,then potential difference between its terminals is 20 V and when a current of 2 A os drawn, potential difference drops to 16 V . The emf of the battery is
Answer» 19.When a current of 0.2A is drawn from a battery ,then potential difference between its terminals is 20 V and when a current of 2 A os drawn, potential difference drops to 16 V . The emf of the battery is

Discussion

1014.	A bullet of 10 g strikes sand-bag at a speed of 103 m/s and gets embedded after travelling 5 cm. Calculate(i) the resistive force exerted by the sand on the bullet(ii) the time taken by the bullet to come
Answer» A bullet of 10 g strikes sand-bag at a speed of $10^{3} m / s$ and gets embedded after travelling 5 cm. Calculate (i) the resistive force exerted by the sand on the bullet (ii) the time taken by the bullet to come

Discussion

1015.	Considering the motion of the object whose velocity-time graph is given in the diagram, calculate the total displacement till 16 seconds?
Answer» Considering the motion of the object whose velocity-time graph is given in the diagram, calculate the total displacement till 16 seconds?

1015.

Considering the motion of the object whose velocity-time graph is given in the diagram, calculate the total displacement till 16 seconds?

Answer»

Considering the motion of the object whose velocity-time graph is given in the diagram, calculate the total displacement till 16 seconds?

Discussion

1016.	Two cars A and B are travelling on a road having their speeds 30 kmph. They are separated by a dis†an ce of 5 km. nother car C is coming in opposite direction with a velocity v and it takes a time of 4 minutes to cross cars A and B. Find the velocity of car C.
Answer» Two cars A and B are travelling on a road having their speeds 30 kmph. They are separated by a dis†an ce of 5 km. nother car C is coming in opposite direction with a velocity v and it takes a time of 4 minutes to cross cars A and B. Find the velocity of car C.

Discussion

1017.	If energy is always conserved in a chemical or physical process then why is there an energy crisis?
Answer» If energy is always conserved in a chemical or physical process then why is there an energy crisis?

Discussion

1018.	A ball is thrown vertically upwards. when the ball reaches one half of its maximum height, its speed becomes 10m/s (a) How high does the ball rise? (b) Find the velocity and acceleration 1s after it is thrown.
Answer» A ball is thrown vertically upwards. when the ball reaches one half of its maximum height, its speed becomes 10m/s (a) How high does the ball rise? (b) Find the velocity and acceleration 1s after it is thrown.

Discussion

1019.	A ray of light is incident on a glass plate at an angle of 60∘. If the reflected and the refracted rays are mutually perpendicular, then the refractive index of material is
Answer» A ray of light is incident on a glass plate at an angle of $60^{\circ}$ . If the reflected and the refracted rays are mutually perpendicular, then the refractive index of material is

Discussion

1020.	Which one is Nearsightedness? A. Myopia B. Hypermetropia C. Astigmatism D. None of these
Answer» Which one is Nearsightedness? A. Myopia B. Hypermetropia C. Astigmatism D. None of these

1020.

Which one is Nearsightedness? A. Myopia B. Hypermetropia C. Astigmatism D. None of these

Answer»

Which one is Nearsightedness?

A. Myopia

B. Hypermetropia

C. Astigmatism

D. None of these

Discussion

1021.	SI unit of density is-
Answer» SI unit of density is-

Discussion

1022.	A train travels with a speed of 60 km h-¹ from station A to station B and then comes back with a speed 80 km h-¹ from station B to station A. Find (i) the average speed,and (i i) the average velocity of train.
Answer» A train travels with a speed of 60 km h-¹ from station A to station B and then comes back with a speed 80 km h-¹ from station B to station A. Find (i) the average speed,and (i i) the average velocity of train.

Discussion

1023.	ntA rope of mass M and length L is being rotated about one end in gravity free space. A pulse is being created at one of the ends. Then angle by which rope will be rotated in the time when pulse reaches the opposite end of rope first time and for the angular velocity of rope V.n
Answer» ntA rope of mass M and length L is being rotated about one end in gravity free space. A pulse is being created at one of the ends. Then angle by which rope will be rotated in the time when pulse reaches the opposite end of rope first time and for the angular velocity of rope V.n

Discussion

1024.	Sir/Ma'am I had previously asked a question of "where exactly does the space expand into....." I received an answer -if space was infinite it wouldn't be expanding into anything because it was already infinite .. But( to the best of my knowledge), i feel that I could simply rule out the space being infinite because- If we had started with some amt of matter then to spread that in an infinite area we would require a density (of space) to be zero exactly , however we even in vaccum find some or the other form of atomic and/or subatomic "substance".... You can object me by telling that we had started with an infinite amount of matter but then we should have a density of exactly 1 unit because -infinity by -infinity=1 Which is not the real case .. What now ,is this some sort of a paradox
Answer» Sir/Ma'am I had previously asked a question of "where exactly does the space expand into....." I received an answer -if space was infinite it wouldn't be expanding into anything because it was already infinite .. But( to the best of my knowledge), i feel that I could simply rule out the space being infinite because- If we had started with some amt of matter then to spread that in an infinite area we would require a density (of space) to be zero exactly , however we even in vaccum find some or the other form of atomic and/or subatomic "substance".... You can object me by telling that we had started with an infinite amount of matter but then we should have a density of exactly 1 unit because -infinity by -infinity=1 Which is not the real case .. What now ,is this some sort of a paradox

Discussion

1025.	How do we differentiate between the sound from a guitar and sound from a flute given that all the parameters of the two instrumentmare are same I.e. frequency , wavelength and amplitude?
Answer» How do we differentiate between the sound from a guitar and sound from a flute given that all the parameters of the two instrumentmare are same I.e. frequency , wavelength and amplitude?

Discussion

1026.	Interference effects are produced at point P on a screen as a result of direct rays from a 500 nm source and reflected rays from the mirror as shown in figure. Assume the source is 100 m to the left of the screen and 1.00 cm above the mirror. Find the distance y to the first dark band above the mirror.
Answer» Interference effects are produced at point $P$ on a screen as a result of direct rays from a $500 nm$ source and reflected rays from the mirror as shown in figure. Assume the source is $100 m$ to the left of the screen and $1.00 cm$ above the mirror. Find the distance $y$ to the first dark band above the mirror.

Discussion

1027.	What is the equivalent resistance between A and B?
Answer» What is the equivalent resistance between $A$ and $B$ ?

Discussion

1028.	Use the following information to answer the next question. An aluminium sheet is heated to 27°C and then a hole is made in the sheet by cutting out a disc of area 16 cm2. The coefficient of linear expansion (α) is 2.5 × 10− 5 /K If the sheet is heated to 225°C, then the area of the hole will
Answer» Use the following information to answer the next question. An aluminium sheet is heated to 27°C and then a hole is made in the sheet by cutting out a disc of area 16 cm². The coefficient of linear expansion (α) is 2.5 × 10^{− 5}/K If the sheet is heated to 225°C, then the area of the hole will

1028.

Use the following information to answer the next question. An aluminium sheet is heated to 27°C and then a hole is made in the sheet by cutting out a disc of area 16 cm2. The coefficient of linear expansion (α) is 2.5 × 10− 5 /K If the sheet is heated to 225°C, then the area of the hole will

Answer»

Use the following information to answer the next question.

An aluminium sheet is heated to 27°C and then a hole is made in the sheet by cutting out a disc of area 16 cm². The coefficient of linear expansion (α) is 2.5 × 10^{− 5}/K

If the sheet is heated to 225°C, then the area of the hole will

Discussion

1029.	On what factors does the focal length of a spherical mirror depends ?
Answer» On what factors does the focal length of a spherical mirror depends ?

Discussion

1030.	What does thermodynamics do in laws of motion.
Answer» What does thermodynamics do in laws of motion.

Discussion

1031.	What is vector quantity ?
Answer» What is vector quantity ?

Discussion

1032.	A construction worker’s helmet slips and falls down when he is 78.4m above the ground. He hears the sound of the helmet hitting the ground 4.23 s after it has slipped. Find the speed of sound in air. ( Take g=9.8 ms−2).
Answer» A construction worker’s helmet slips and falls down when he is $78.4 m$ above the ground. He hears the sound of the helmet hitting the ground $4.23 s$ after it has slipped. Find the speed of sound in air. ( Take $g = 9.8 m s^{- 2}$ ).

Discussion

1033.	Explain how sound is produced in a school bell.
Answer» Explain how sound is produced in a school bell.

Discussion

1034.	The value of Gravitational constant depends upon
Answer» The value of Gravitational constant depends upon

Discussion

1035.	Sports facilities built for the Olympics are not fully utilised after the Games are over because
Answer» Sports facilities built for the Olympics are not fully utilised after the Games are over because

Discussion

1036.	Magnetic field lines represent uniform field strength when they
Answer» Magnetic field lines represent uniform field strength when they

Discussion

1037.	If the mass of a body is 5kg, its weight on the surface of the earth would be ___ N (newton). (g=9.8m/s2)
Answer» If the mass of a body is 5kg, its weight on the surface of the earth would be ___ N (newton). $(g = 9.8 m / s^{2})$

Discussion

1038.	ntresistance of a wire of lenght 1 mm is 26 ohm at 20 degree celsius. if the diameter of the wire is 0.3 mm then what will be the resistivity of the metal at that temperature?n
Answer» ntresistance of a wire of lenght 1 mm is 26 ohm at 20 degree celsius. if the diameter of the wire is 0.3 mm then what will be the resistivity of the metal at that temperature?n

Discussion

1039.	A body falls freely from a tower and travels a distance of 40 in its last two seconds. The height of the tower is
Answer» A body falls freely from a tower and travels a distance of $40$ in its last two seconds. The height of the tower is

Discussion

1040.	In how much time (in seconds) should a charge of 10 coulombs flow between two terminals of a circuit so as to maintain a constant current of 100 A?
Answer» In how much time (in seconds) should a charge of $10$ coulombs flow between two terminals of a circuit so as to maintain a constant current of $100 A ?$

Discussion

1041.	Why electric field lines do not intersect each other ?
Answer» Why electric field lines do not intersect each other ?

Discussion

1042.	A cheetah starts from rest, and accelerates at 2 m/s2 for 10 secibds, Calculate : (a) the final velocity (b) the distance travelled.
Answer» A cheetah starts from rest, and accelerates at 2 $m / s^{2}$ for 10 secibds, Calculate : (a) the final velocity (b) the distance travelled.

1042.

A cheetah starts from rest, and accelerates at 2 m/s2 for 10 secibds, Calculate : (a) the final velocity (b) the distance travelled.

Answer»

A cheetah starts from rest, and accelerates at 2 $m / s^{2}$ for 10 secibds, Calculate :

(a) the final velocity

(b) the distance travelled.

Discussion

1043.	89.What is aperture of a spherical mirror?
Answer» 89.What is aperture of a spherical mirror?

Discussion

1044.	What happens to the kinetic energy when the mass of the body is doubled but the velocity is reduced to half?
Answer» What happens to the kinetic energy when the mass of the body is doubled but the velocity is reduced to half?

Discussion

1045.	If 92X206 undergoes successively 8 α - decays and 6 β - decays, then resulting nucleus is
Answer» If $_{92} X^{206}$ undergoes successively 8 $α$ - decays and 6 $β$ - decays, then resulting nucleus is

Discussion

1046.	How is an elephant able to hear sounds from a far distance?
Answer» How is an elephant able to hear sounds from a far distance?

Discussion

1047.	An insect moves along the sides of a wall of dimensions 12 m × 5 m starting from one corner and reaches the diagonally opposite corner. If the insect takes 2 s for its motion, then find the ratio of average speed to the average velocity of insect.
Answer» An insect moves along the sides of a wall of dimensions 12 m $\times$ 5 m starting from one corner and reaches the diagonally opposite corner. If the insect takes 2 s for its motion, then find the ratio of average speed to the average velocity of insect.

Discussion

1048.	A sphere of mass 5 kg and volume 2.2×10−4 m3 is completely immersed in water. Find the buoyant force exerted by water on the sphere.Density of water =1000 kg-m−3 and take g=10 m/s2
Answer» A sphere of mass $5 kg$ and volume $2.2 \times 10^{- 4} m^{3}$ is completely immersed in water. Find the buoyant force exerted by water on the sphere. Density of water $= 1000 {kg-m}^{- 3}$ and take $g = 10 {m/s}^{2}$

Discussion

1049.	A 5 g piece of ice at - 20∘C is put into 10g of water at 30∘C. Assuming that heat is exchanged only between the ice and the water, find the final temperature of the mixture.
Answer» A 5 g piece of ice at - $20^{\circ} C$ is put into 10g of water at $30^{\circ} C$ . Assuming that heat is exchanged only between the ice and the water, find the final temperature of the mixture.

Discussion

1050.	A source of wave produces 40 crests and 40 troughs in 0.4 seconds. What is the frequency of the wave?
Answer» A source of wave produces 40 crests and 40 troughs in 0.4 seconds. What is the frequency of the wave?

Discussion

Explore topic-wise InterviewSolutions in .

A ball is dropped from a height of 10 m. If the energy of the ball reduces by 40% after striking the ground, how much high can the ball bounce back (in meters)? (Take g = 10 ms2​)

What are the characteristics of image formed by concave lens?

For the given object (O) and mirror arrangement, the velocity of the image with respect to ground will be [All the velocities are given with respect to ground]

The international space station is maintained in a nearly circular orbit with a mean altitude of 330 km and a maximum of 410 km. An astronaut is floating in the space station’s cabin. The acceleration of astronaut as measured from the earth is.

36.What is the path followed by a moving body, on which a constant force acts in a direction other than initial velocity(i.e. excluding parallel and antiparallel direction)? (1) Straight line (2) Parabolic (3) Circular (4) Elliptical

A Quantity which has both magnitude and direction is called.

In the experiment to study the variation in square of time period of simple pendulum with its length:

A capacitor of capacitance C, is connected across an AC source of voltage V, given by V=V0sinωt. The displacement current between the plates of the capacitor, would then be given by

Can a magnet be used to magnetize a piece of iron? How?

Draw the displacement-time graph for the values given below. Displacement after 1 s,2 s,3 s and 4 s are 5 m,10 m,15 m and 20 m respectively. [2 MARKS]

Find out the appropriate word which fits the 1st blank.

19.When a current of 0.2A is drawn from a battery ,then potential difference between its terminals is 20 V and when a current of 2 A os drawn, potential difference drops to 16 V . The emf of the battery is

A bullet of 10 g strikes sand-bag at a speed of 103 m/s and gets embedded after travelling 5 cm. Calculate(i) the resistive force exerted by the sand on the bullet(ii) the time taken by the bullet to come

Considering the motion of the object whose velocity-time graph is given in the diagram, calculate the total displacement till 16 seconds?

Two cars A and B are travelling on a road having their speeds 30 kmph. They are separated by a dis†an ce of 5 km. nother car C is coming in opposite direction with a velocity v and it takes a time of 4 minutes to cross cars A and B. Find the velocity of car C.

If energy is always conserved in a chemical or physical process then why is there an energy crisis?

A ball is thrown vertically upwards. when the ball reaches one half of its maximum height, its speed becomes 10m/s (a) How high does the ball rise? (b) Find the velocity and acceleration 1s after it is thrown.

A ray of light is incident on a glass plate at an angle of 60∘. If the reflected and the refracted rays are mutually perpendicular, then the refractive index of material is

Which one is Nearsightedness? A. Myopia B. Hypermetropia C. Astigmatism D. None of these

SI unit of density is-

A train travels with a speed of 60 km h-¹ from station A to station B and then comes back with a speed 80 km h-¹ from station B to station A. Find (i) the average speed,and (i i) the average velocity of train.

ntA rope of mass M and length L is being rotated about one end in gravity free space. A pulse is being created at one of the ends. Then angle by which rope will be rotated in the time when pulse reaches the opposite end of rope first time and for the angular velocity of rope V.n

How do we differentiate between the sound from a guitar and sound from a flute given that all the parameters of the two instrumentmare are same I.e. frequency , wavelength and amplitude?

What is the equivalent resistance between A and B?

Use the following information to answer the next question. An aluminium sheet is heated to 27°C and then a hole is made in the sheet by cutting out a disc of area 16 cm2. The coefficient of linear expansion (α) is 2.5 × 10− 5 /K If the sheet is heated to 225°C, then the area of the hole will

On what factors does the focal length of a spherical mirror depends ?

What does thermodynamics do in laws of motion.

What is vector quantity ?

A construction worker’s helmet slips and falls down when he is 78.4m above the ground. He hears the sound of the helmet hitting the ground 4.23 s after it has slipped. Find the speed of sound in air. ( Take g=9.8 ms−2).

Explain how sound is produced in a school bell.

The value of Gravitational constant depends upon

Sports facilities built for the Olympics are not fully utilised after the Games are over because

Magnetic field lines represent uniform field strength when they

If the mass of a body is 5kg, its weight on the surface of the earth would be ___ N (newton). (g=9.8m/s2)

ntresistance of a wire of lenght 1 mm is 26 ohm at 20 degree celsius. if the diameter of the wire is 0.3 mm then what will be the resistivity of the metal at that temperature?n

A body falls freely from a tower and travels a distance of 40 in its last two seconds. The height of the tower is

In how much time (in seconds) should a charge of 10 coulombs flow between two terminals of a circuit so as to maintain a constant current of 100 A?

Why electric field lines do not intersect each other ?

A cheetah starts from rest, and accelerates at 2 m/s2 for 10 secibds, Calculate : (a) the final velocity (b) the distance travelled.

89.What is aperture of a spherical mirror?

What happens to the kinetic energy when the mass of the body is doubled but the velocity is reduced to half?

If 92X206 undergoes successively 8 α - decays and 6 β - decays, then resulting nucleus is

How is an elephant able to hear sounds from a far distance?

An insect moves along the sides of a wall of dimensions 12 m × 5 m starting from one corner and reaches the diagonally opposite corner. If the insect takes 2 s for its motion, then find the ratio of average speed to the average velocity of insect.

A sphere of mass 5 kg and volume 2.2×10−4 m3 is completely immersed in water. Find the buoyant force exerted by water on the sphere.Density of water =1000 kg-m−3 and take g=10 m/s2

A 5 g piece of ice at - 20∘C is put into 10g of water at 30∘C. Assuming that heat is exchanged only between the ice and the water, find the final temperature of the mixture.

A source of wave produces 40 crests and 40 troughs in 0.4 seconds. What is the frequency of the wave?

A ball is dropped from a height of 10 m. If the energy of the ball reduces by 40% after striking the ground, how much high can the ball bounce back (in meters)? (Take g = 10 ms2)