9478 + Interview Questions in Physics Page 49 InterviewSolution

2401.	Regardez l'image et répondez.1. Est-ce que c'est une boulangerie?2. Que trouve-t-on ici?
Answer» Regardez l'image et répondez. 1. Est-ce que c'est une boulangerie? 2. Que trouve-t-on ici?

Discussion

2402.	A soap bubble of radius R is surrounded by another soap bubble of radius 2R, as shown. Take surface tension = S. The pressure inside the smaller soap bubble, in excess of the atmospheric pressure is nSR, then find the value of n.
Answer» A soap bubble of radius R is surrounded by another soap bubble of radius 2R, as shown. Take surface tension = S. The pressure inside the smaller soap bubble, in excess of the atmospheric pressure is $\frac{n S}{R}$ , then find the value of n.

Discussion

2403.	Kinetic theory of matter states that molecules are in constant motion and posses kinetic energy. But where did these molecules get the energy from?
Answer» Kinetic theory of matter states that molecules are in constant motion and posses kinetic energy. But where did these molecules get the energy from?

Discussion

2404.	Two masses, 800 kg and 600 kg, are at a distance 0.25 m apart. Compute the magnitude of the intensity of the gravitational field at a point distant 0.20 m from the 800 kg mass and 0.15 m from the 600 kg mass.
Answer» Two masses, 800 kg and 600 kg, are at a distance 0.25 m apart. Compute the magnitude of the intensity of the gravitational field at a point distant 0.20 m from the 800 kg mass and 0.15 m from the 600 kg mass.

Discussion

2405.	Increased concentration of carbon dioxide in the air causes
Answer» Increased concentration of carbon dioxide in the air causes

Discussion

2406.	Write answers to the following questions .(a) How is sound produced ?(b) What does the intensity of sound depend upon ?(c) Explain how the frequency of oscillation is related to the length of a pendulum and the amplitude of its oscillation.(d) Explain the two ways by which the pitch of the sound generated by a stretched string can be changed.
Answer» Write answers to the following questions . (a) How is sound produced ? (b) What does the intensity of sound depend upon ? (c) Explain how the frequency of oscillation is related to the length of a pendulum and the amplitude of its oscillation. (d) Explain the two ways by which the pitch of the sound generated by a stretched string can be changed.

Discussion

2407.	Why does the magnitude of friction reduce when an inclined plane is used?
Answer» Why does the magnitude of friction reduce when an inclined plane is used?

Discussion

2408.	A charge q is placed at the centre of the open end of a cylindrical vessel. The flux of the electric field through the surface of the vessel is
Answer» A charge q is placed at the centre of the open end of a cylindrical vessel. The flux of the electric field through the surface of the vessel is

Discussion

2409.	two identical capacitors of capaci†an ce C are connected in parallel with battery of voltage v in parallel with them and a key is present in between the capacitors. when key is closed and capacitors are fully charged their net stored energy is U1. if now key is opened and a material of dielectric cons†an t 2 is inserted in each capacitors their net stored energy is U2. then u1/ u2 is ?
Answer» two identical capacitors of capaci†an ce C are connected in parallel with battery of voltage v in parallel with them and a key is present in between the capacitors. when key is closed and capacitors are fully charged their net stored energy is U1. if now key is opened and a material of dielectric cons†an t 2 is inserted in each capacitors their net stored energy is U2. then u1/ u2 is ?

Discussion

2410.	Give reasons. (a) Letters appear laterally inverted in a plane mirror. (b) Numerous images are seen in the ‘Palace of Mirrors’. (c) The image formed in water is of the same size as the object. (d) We do not see an image in transparent glass.
Answer» Give reasons. (a) Letters appear laterally inverted in a plane mirror. (b) Numerous images are seen in the ‘Palace of Mirrors’. (c) The image formed in water is of the same size as the object. (d) We do not see an image in transparent glass.

2410.

Give reasons. (a) Letters appear laterally inverted in a plane mirror. (b) Numerous images are seen in the ‘Palace of Mirrors’. (c) The image formed in water is of the same size as the object. (d) We do not see an image in transparent glass.

Answer»

Give reasons.

(a) Letters appear laterally inverted in a plane mirror.

(b) Numerous images are seen in the ‘Palace of Mirrors’.

(c) The image formed in water is of the same size as the object.

(d) We do not see an image in transparent glass.

Discussion

2411.	What is the definition of solidification?
Answer» What is the definition of solidification?

Discussion

2412.	What do you mean by the conductor? Explain with suitable examples.
Answer» What do you mean by the conductor? Explain with suitable examples.

Discussion

2413.	35. The second overtone of a closed pipeand the third overtone of an open pipeare in unison. The ratio of their funda-mental frequencies are(a) 5:4(c) 25: 16(b) 4:5(d) 16:25
Answer» 35. The second overtone of a closed pipeand the third overtone of an open pipeare in unison. The ratio of their funda-mental frequencies are(a) 5:4(c) 25: 16(b) 4:5(d) 16:25

Discussion

2414.	What is the unit of Electric Charge?
Answer» What is the unit of Electric Charge?

Discussion

2415.	35.Three cells having emf 2V, 1V and 4V and internal resistances 4, 3 and 2 ohm respe. are connected in parallel with their positive ends connected together. Find the current through each cell.
Answer» 35.Three cells having emf 2V, 1V and 4V and internal resistances 4, 3 and 2 ohm respe. are connected in parallel with their positive ends connected together. Find the current through each cell.

Discussion

2416.	The force of attraction between the two bodies at a certain separation is 10N.What will be the force of attraction between them if the separation is reduced to half
Answer» The force of attraction between the two bodies at a certain separation is 10N.What will be the force of attraction between them if the separation is reduced to half

Discussion

2417.	Four point charges are placed at the vertices of a square of side √2 m as shown in figure.What will be the magnitude of force experienced by a charge +q placed at the centre of the square ?Here k=14πϵo
Answer» Four point charges are placed at the vertices of a square of side $\sqrt{2} m$ as shown in figure. What will be the magnitude of force experienced by a charge $+ q$ placed at the centre of the square ? Here $k = \frac{1}{4 π ϵ_{o}}$

Discussion

2418.	An object in Marks 5 kg which is kept on a table in 3 cm area find out the pressure applied by object on table
Answer» An object in Marks 5 kg which is kept on a table in 3 cm area find out the pressure applied by object on table

Discussion

2419.	Speed v=\sqrt{A-Bx}, where A&B are constants, find acceleration
Answer» Speed v=\sqrt{A-Bx}, where A&B are constants, find acceleration

Discussion

2420.	WHY DOES A ROLLING SPHERE SLOWS DOWN ON A ROUGH SURFACE DESPITE OF THE FACT THAT FRICTION PROVIDES IT TORQUE ALONG THE DIRECTION OF MOTION? KINDLY PROVIDE DIAGRAM IF POSSIBE.
Answer» WHY DOES A ROLLING SPHERE SLOWS DOWN ON A ROUGH SURFACE DESPITE OF THE FACT THAT FRICTION PROVIDES IT TORQUE ALONG THE DIRECTION OF MOTION? KINDLY PROVIDE DIAGRAM IF POSSIBE.

Discussion

2421.	Q. A car is moving on a road with a speed 40 m/s, blows a horn of frequency 200 Hz. The apparent wavelength of sound as observed by a detector on the road behind the car will be (Speed of sound in air is 340 m/s)Options: 1.5 m 1.9 m2.6 m4.1 m
Answer» Q. A car is moving on a road with a speed 40 m/s, blows a horn of frequency 200 Hz. The apparent wavelength of sound as observed by a detector on the road behind the car will be (Speed of sound in air is 340 m/s) Options: 1.5 m 1.9 m 2.6 m 4.1 m

Discussion

2422.	The eye of a person exhibits a phenomenon X due to which it can see the image of an object for a short duration of Y even after the object has disappeared from his view. It is due to the phenomenon X that we are able to see moving Z on a television screen. What are X, Y and Z ?
Answer» The eye of a person exhibits a phenomenon X due to which it can see the image of an object for a short duration of Y even after the object has disappeared from his view. It is due to the phenomenon X that we are able to see moving Z on a television screen. What are X, Y and Z ?

Discussion

2423.	Statement 1: Venus is the brightest planet in the night sky.Statement 2: Venus is often called morning or evening star, although it is not a star.
Answer» Statement 1: Venus is the brightest planet in the night sky. Statement 2: Venus is often called morning or evening star, although it is not a star.

2423.

Statement 1: Venus is the brightest planet in the night sky.Statement 2: Venus is often called morning or evening star, although it is not a star.

Answer»

Statement 1: Venus is the brightest planet in the night sky.

Statement 2: Venus is often called morning or evening star, although it is not a star.

Discussion

2424.	The middle surface of a plane mirror is covered with a dark paper. How many images of yourself will you see in the mirror if earlier you could only see one image of yourself on that mirror?
Answer» The middle surface of a plane mirror is covered with a dark paper. How many images of yourself will you see in the mirror if earlier you could only see one image of yourself on that mirror?

2424.

The middle surface of a plane mirror is covered with a dark paper. How many images of yourself will you see in the mirror if earlier you could only see one image of yourself on that mirror?

Answer»

The middle surface of a plane mirror is covered with a dark paper. How many images of yourself will you see in the mirror if earlier you could only see one image of yourself on that mirror?

Discussion

2425.	(a) Explain how you can locate the Pole star with the help of Ursa Major constellation. (b) Explain how the position of Sirius star can be located in the night sky with help of Orion constellation.
Answer» (a) Explain how you can locate the Pole star with the help of Ursa Major constellation. (b) Explain how the position of Sirius star can be located in the night sky with help of Orion constellation.

2425.

(a) Explain how you can locate the Pole star with the help of Ursa Major constellation. (b) Explain how the position of Sirius star can be located in the night sky with help of Orion constellation.

Answer»

(a) Explain how you can locate the Pole star with the help of Ursa Major constellation.

(b) Explain how the position of Sirius star can be located in the night sky with help of Orion constellation.

Discussion

2426.	An artificial satellite is moving in a circular orbit of radius 42250 km. Calculate its speed if it takes 24 hours for one revolution..
Answer» An artificial satellite is moving in a circular orbit of radius 42250 km. Calculate its speed if it takes 24 hours for one revolution..

Discussion

2427.	How many minimum number of mirrors are required to check if a barber has cut hair on your neck properly or not?
Answer» How many minimum number of mirrors are required to check if a barber has cut hair on your neck properly or not?

Discussion

2428.	Define melting.
Answer» Define melting.

Discussion

2429.	Identify the name of the device that can be used to test whether an object is carrying a charge or not.
Answer» Identify the name of the device that can be used to test whether an object is carrying a charge or not.

Discussion

2430.	Electric supply of a house is through a 15 A fuse. When a 2000 W heater is used in this house, how many 100 W bulbs can be used simultaneously?The supply is at 220 V, the heater and the bulbs are rated for 220 V.
Answer» Electric supply of a house is through a $15 A$ fuse. When a $2000 W$ heater is used in this house, how many $100 W$ bulbs can be used simultaneously? The supply is at $220 V$ , the heater and the bulbs are rated for $220 V$ .

Discussion

2431.	Define the following terms:(a) Zenith(b) Nadir(c) Celestial poles
Answer» Define the following terms: (a) Zenith (b) Nadir (c) Celestial poles

Discussion

2432.	If you rub a metal comb in your hair it does not get charged why
Answer» If you rub a metal comb in your hair it does not get charged why

Discussion

2433.	A wave of frequency 500 Hz has velocity 360 m/s. The distance between two nearest points 60° out of phase, is ?
Answer» A wave of frequency 500 Hz has velocity 360 m/s. The distance between two nearest points 60° out of phase, is ?

Discussion

2434.	Find nfactor of Fe2S3 in given reaction. Fe2S3 + O2 —} FeSO4 + SO2
Answer» Find nfactor of Fe2S3 in given reaction. Fe2S3 + O2 —} FeSO4 + SO2

Discussion

2435.	A particle of mass 1 kg was sliding with a velocity of 10 ms−1 on a rough floor. It comes to rest after 5 s. The rate at which floor warms up is:
Answer» A particle of mass $1 k g$ was sliding with a velocity of $10 m s^{- 1}$ on a rough floor. It comes to rest after $5 s$ . The rate at which floor warms up is:

Discussion

2436.	A concert hall ceiling is often fully covered with inverted clay pots because.
Answer» A concert hall ceiling is often fully covered with inverted clay pots because.

Discussion

2437.	A machine lifts up a load of 500 kg by a height of 2 m. Calculate the efficiency of the machine if the energy input to the machine is 25000 J. (Take g=10 ms−2).0.4
Answer» A machine lifts up a load of $500 k g$ by a height of $2 m$ . Calculate the efficiency of the machine if the energy input to the machine is $25000 J$ . (Take $g = 10 m s^{- 2}$ ). 0.4

Discussion

2438.	The boiling point of an aqueous solution of a non volatile solute is 100.15 degree celsius. What is the freezing point of an aqueous solution obtained by diluting the above solution with an equal volume of water ? The values of Kb and Kf are given as 0.512 and 1.86 K molality -1.
Answer» The boiling point of an aqueous solution of a non volatile solute is 100.15 degree celsius. What is the freezing point of an aqueous solution obtained by diluting the above solution with an equal volume of water ? The values of Kb and Kf are given as 0.512 and 1.86 K molality -1.

Discussion

2439.	what happen to the leaves when a negatively charged rod is brought near1) a positively charged electroscope2) a negatively charged electroscope3) an uncharged electroscope What does an earthed electroscope mean?
Answer» what happen to the leaves when a negatively charged rod is brought near 1) a positively charged electroscope 2) a negatively charged electroscope 3) an uncharged electroscope What does an earthed electroscope mean?

Discussion

2440.	The amplitude of a sound wave determines its ___.
Answer» The amplitude of a sound wave determines its ___.

Discussion

2441.	{ In an experiment of Ohm's law, Voltmeter across a resistance measure }(10\pm0.1) volt and ammeter measures }}{ the current through resistor }(5\pm0.2) ampere. The value of resistance is
Answer» { In an experiment of Ohm's law, Voltmeter across a resistance measure }(10\pm0.1) volt and ammeter measures }}{ the current through resistor }(5\pm0.2) ampere. The value of resistance is

Discussion

2442.	An object P is focussed by a microscope M. A glass slab of thickness 2.1 cm is introduced between P and M. If the refractive index of the slab is 1.5, by what distance should the microscope be shifted to focus the object again ?
Answer» An object P is focussed by a microscope M. A glass slab of thickness 2.1 cm is introduced between P and M. If the refractive index of the slab is 1.5, by what distance should the microscope be shifted to focus the object again ?

Discussion

2443.	What happens in expansion of heat?
Answer» What happens in expansion of heat?

Discussion

2444.	Why do kabaddi players apply coarse powder or dry soil on their hands before starting a game?
Answer» Why do kabaddi players apply coarse powder or dry soil on their hands before starting a game?

Discussion

2445.	Why is it advised to tie any luggage kept on the roof of a bus with a rope?
Answer» Why is it advised to tie any luggage kept on the roof of a bus with a rope?

Discussion

2446.	2. Two metal balls with radii ri and r2 are at adistance R from each other and are connected toa battery of e.m.f. E. The force of interactionbetween the balls (ri and r2
Answer» 2. Two metal balls with radii ri and r2 are at a distance R from each other and are connected to a battery of e.m.f. E. The force of interaction between the balls (ri and r2<< R) 2TEr2 (L) R2 (G+2) (2) 4 TE E2 16T2E2 () R2 (r+ 22 03. (E)

Discussion

2447.	For the system shown in the figure, Y(s)/X(s) =1
Answer» For the system shown in the figure, $Y (s) / X (s)$ = 1

2447.

For the system shown in the figure, Y(s)/X(s) =1

Answer»

For the system shown in the figure, $Y (s) / X (s)$ =

1

Discussion

2448.	14.Why do charges reside only on the surface of the conductor?
Answer» 14.Why do charges reside only on the surface of the conductor?

Discussion

2449.	A ray of laser light misses a target by about 3∘ after reflecting off a polished surface as shown. If only the surface can be rotated, in what way it should be done for the light to hit the target? (+ indicates clockwise direction, and − indicates anticlockwise direction)-1.5
Answer» A ray of laser light misses a target by about $3^{\circ}$ after reflecting off a polished surface as shown. If only the surface can be rotated, in what way it should be done for the light to hit the target? ( $+$ indicates clockwise direction, and $-$ indicates anticlockwise direction) -1.5

2449.

A ray of laser light misses a target by about 3∘ after reflecting off a polished surface as shown. If only the surface can be rotated, in what way it should be done for the light to hit the target? (+ indicates clockwise direction, and − indicates anticlockwise direction)-1.5

Answer» A ray of laser light misses a target by about

3^{\circ}

after reflecting off a polished surface as shown. If only the surface can be rotated, in what way it should be done for the light to hit the target?

(

+

indicates clockwise direction, and

-

indicates anticlockwise direction)

-1.5

Discussion

2450.	Pressure on a surface due to a force is reduced if ___ increases.
Answer» Pressure on a surface due to a force is reduced if ___ increases.

Discussion

Explore topic-wise InterviewSolutions in .

Regardez l'image et répondez.1. Est-ce que c'est une boulangerie?2. Que trouve-t-on ici?

A soap bubble of radius R is surrounded by another soap bubble of radius 2R, as shown. Take surface tension = S. The pressure inside the smaller soap bubble, in excess of the atmospheric pressure is nSR, then find the value of n.

Kinetic theory of matter states that molecules are in constant motion and posses kinetic energy. But where did these molecules get the energy from?

Two masses, 800 kg and 600 kg, are at a distance 0.25 m apart. Compute the magnitude of the intensity of the gravitational field at a point distant 0.20 m from the 800 kg mass and 0.15 m from the 600 kg mass.

Increased concentration of carbon dioxide in the air causes

Why does the magnitude of friction reduce when an inclined plane is used?

A charge q is placed at the centre of the open end of a cylindrical vessel. The flux of the electric field through the surface of the vessel is

Give reasons. (a) Letters appear laterally inverted in a plane mirror. (b) Numerous images are seen in the ‘Palace of Mirrors’. (c) The image formed in water is of the same size as the object. (d) We do not see an image in transparent glass.

What is the definition of solidification?

What do you mean by the conductor? Explain with suitable examples.

35. The second overtone of a closed pipeand the third overtone of an open pipeare in unison. The ratio of their funda-mental frequencies are(a) 5:4(c) 25: 16(b) 4:5(d) 16:25

What is the unit of Electric Charge?

35.Three cells having emf 2V, 1V and 4V and internal resistances 4, 3 and 2 ohm respe. are connected in parallel with their positive ends connected together. Find the current through each cell.

The force of attraction between the two bodies at a certain separation is 10N.What will be the force of attraction between them if the separation is reduced to half

Four point charges are placed at the vertices of a square of side √2 m as shown in figure.What will be the magnitude of force experienced by a charge +q placed at the centre of the square ?Here k=14πϵo

An object in Marks 5 kg which is kept on a table in 3 cm area find out the pressure applied by object on table

Speed v=\sqrt{A-Bx}, where A&B are constants, find acceleration

WHY DOES A ROLLING SPHERE SLOWS DOWN ON A ROUGH SURFACE DESPITE OF THE FACT THAT FRICTION PROVIDES IT TORQUE ALONG THE DIRECTION OF MOTION? KINDLY PROVIDE DIAGRAM IF POSSIBE.

Q. A car is moving on a road with a speed 40 m/s, blows a horn of frequency 200 Hz. The apparent wavelength of sound as observed by a detector on the road behind the car will be (Speed of sound in air is 340 m/s)Options: 1.5 m 1.9 m2.6 m4.1 m

The eye of a person exhibits a phenomenon X due to which it can see the image of an object for a short duration of Y even after the object has disappeared from his view. It is due to the phenomenon X that we are able to see moving Z on a television screen. What are X, Y and Z ?

Statement 1: Venus is the brightest planet in the night sky.Statement 2: Venus is often called morning or evening star, although it is not a star.

The middle surface of a plane mirror is covered with a dark paper. How many images of yourself will you see in the mirror if earlier you could only see one image of yourself on that mirror?

(a) Explain how you can locate the Pole star with the help of Ursa Major constellation. (b) Explain how the position of Sirius star can be located in the night sky with help of Orion constellation.

An artificial satellite is moving in a circular orbit of radius 42250 km. Calculate its speed if it takes 24 hours for one revolution..

How many minimum number of mirrors are required to check if a barber has cut hair on your neck properly or not?

Define melting.

Identify the name of the device that can be used to test whether an object is carrying a charge or not.

Electric supply of a house is through a 15 A fuse. When a 2000 W heater is used in this house, how many 100 W bulbs can be used simultaneously?The supply is at 220 V, the heater and the bulbs are rated for 220 V.

Define the following terms:(a) Zenith(b) Nadir(c) Celestial poles

If you rub a metal comb in your hair it does not get charged why

A wave of frequency 500 Hz has velocity 360 m/s. The distance between two nearest points 60° out of phase, is ?

Find nfactor of Fe2S3 in given reaction. Fe2S3 + O2 —} FeSO4 + SO2

A particle of mass 1 kg was sliding with a velocity of 10 ms−1 on a rough floor. It comes to rest after 5 s. The rate at which floor warms up is:

A concert hall ceiling is often fully covered with inverted clay pots because.

A machine lifts up a load of 500 kg by a height of 2 m. Calculate the efficiency of the machine if the energy input to the machine is 25000 J. (Take g=10 ms−2).0.4

The boiling point of an aqueous solution of a non volatile solute is 100.15 degree celsius. What is the freezing point of an aqueous solution obtained by diluting the above solution with an equal volume of water ? The values of Kb and Kf are given as 0.512 and 1.86 K molality -1.

what happen to the leaves when a negatively charged rod is brought near1) a positively charged electroscope2) a negatively charged electroscope3) an uncharged electroscope What does an earthed electroscope mean?

The amplitude of a sound wave determines its ___.

{ In an experiment of Ohm's law, Voltmeter across a resistance measure }(10\pm0.1) volt and ammeter measures }}{ the current through resistor }(5\pm0.2) ampere. The value of resistance is

An object P is focussed by a microscope M. A glass slab of thickness 2.1 cm is introduced between P and M. If the refractive index of the slab is 1.5, by what distance should the microscope be shifted to focus the object again ?

What happens in expansion of heat?

Why do kabaddi players apply coarse powder or dry soil on their hands before starting a game?

Why is it advised to tie any luggage kept on the roof of a bus with a rope?

2. Two metal balls with radii ri and r2 are at adistance R from each other and are connected toa battery of e.m.f. E. The force of interactionbetween the balls (ri and r2

For the system shown in the figure, Y(s)/X(s) =1

14.Why do charges reside only on the surface of the conductor?

A ray of laser light misses a target by about 3∘ after reflecting off a polished surface as shown. If only the surface can be rotated, in what way it should be done for the light to hit the target? (+ indicates clockwise direction, and − indicates anticlockwise direction)-1.5

Pressure on a surface due to a force is reduced if ___ increases.