9478 + Interview Questions in Physics Page 57 InterviewSolution

2801.	Write answers the following questions. (a) Why does friction cause a charge to develop? (b) Why is the charge developed due to friction called a static electric charge? (c) Why does the charge developed by induction disappear quickly? (d) Why do the leaves of a gold leaf electroscope fly apart when a charged body touches its disc? (e) What causes the cracking sound we hear as we wear a cardigan?
Answer» Write answers the following questions. (a) Why does friction cause a charge to develop? (b) Why is the charge developed due to friction called a static electric charge? (c) Why does the charge developed by induction disappear quickly? (d) Why do the leaves of a gold leaf electroscope fly apart when a charged body touches its disc? (e) What causes the cracking sound we hear as we wear a cardigan?

2801.

Write answers the following questions. (a) Why does friction cause a charge to develop? (b) Why is the charge developed due to friction called a static electric charge? (c) Why does the charge developed by induction disappear quickly? (d) Why do the leaves of a gold leaf electroscope fly apart when a charged body touches its disc? (e) What causes the cracking sound we hear as we wear a cardigan?

Answer»

Write answers the following questions.

(a) Why does friction cause a charge to develop?

(b) Why is the charge developed due to friction called a static electric charge?

(c) Why does the charge developed by induction disappear quickly?

(d) Why do the leaves of a gold leaf electroscope fly apart when a charged body touches its disc?

(e) What causes the cracking sound we hear as we wear a cardigan?

Discussion

2802.	Two particles of equal mass m go around a circle of radius R under the action of their mutual gravitationaattraction. The speed of each particle with respect to their centre of mass is(1) GmGm4R(3)Gm3RarGm2R
Answer» Two particles of equal mass m go around a circle of radius R under the action of their mutual gravitationaattraction. The speed of each particle with respect to their centre of mass is(1) GmGm4R(3)Gm3RarGm2R

Discussion

2803.	A block of mass m is resting on a horizontal surface. The coefficient of friction is 0.4. A horizontal force of 10N is needed to move the block. Normal reaction N acting is
Answer» A block of mass $m$ is resting on a horizontal surface. The coefficient of friction is 0.4. A horizontal force of $10 N$ is needed to move the block. Normal reaction $N$ acting is

Discussion

2804.	8.State true OR false and if true give reason and if false give reason (1) All dissymmetrical objects are optically active. (2) All asymmetrical objects are optically active.
Answer» 8.State true OR false and if true give reason and if false give reason (1) All dissymmetrical objects are optically active. (2) All asymmetrical objects are optically active.

Discussion

2805.	Why kinetic energy of a system is not equal to 1/2 M total ×V^2com
Answer» Why kinetic energy of a system is not equal to 1/2 M total ×V^2com

Discussion

2806.	A beaker contains water up to a height h1 and K.oil above water up to another height h2. Find the apparent shift in the position of the bottom of the beaker when viewed from above. Refractive index of water is μ1 and that of K.oil is μ2.
Answer» A beaker contains water up to a height $h_{1}$ and K.oil above water up to another height $h_{2} .$ Find the apparent shift in the position of the bottom of the beaker when viewed from above. Refractive index of water is $μ_{1}$ and that of K.oil is $μ_{2} .$

Discussion

2807.	Pritish pulls a load up an inclined road. What is/are the force(s) he must overcome to pull it up?
Answer» Pritish pulls a load up an inclined road. What is/are the force(s) he must overcome to pull it up?

Discussion

2808.	Five charged particles each +Q and one –Q are placed at the six corners of a regular hexagon of sides length a. The electrostatic force over q0 placed at the centre is given by
Answer» Five charged particles each +Q and one –Q are placed at the six corners of a regular hexagon of sides length a. The electrostatic force over q0 placed at the centre is given by

Discussion

2809.	Is angular acceleration of a particle moving along a circular path with uniform speed -- zero/variable ?
Answer» Is angular acceleration of a particle moving along a circular path with uniform speed -- zero/variable ?

Discussion

2810.	In an electric circuit 3 incandescent bulbs A B C of rating A( 40W ,200V) B(50W ,200V) C(100W,200V) are connected in series with a 200V supply what is the power dissipated across 50 watt bulb
Answer» In an electric circuit 3 incandescent bulbs A B C of rating A( 40W ,200V) B(50W ,200V) C(100W,200V) are connected in series with a 200V supply what is the power dissipated across 50 watt bulb

Discussion

2811.	Question 16 Boojho stands at A just on the side of a plane mirror as shown in Fig. 16.20. Can he see himself in the mirror? Also can he see the image of objects situated at P, Q and R?
Answer» Question 16 Boojho stands at A just on the side of a plane mirror as shown in Fig. 16.20. Can he see himself in the mirror? Also can he see the image of objects situated at P, Q and R?

Discussion

2812.	State the parts of the rocket.
Answer» State the parts of the rocket.

Discussion

2813.	12. In the equilibirum mixture CacO_{3(s)→}CaO(s) + CO,(g). Pressure ofCO_2(g) at 27^° C is 2 atm. What will be the pressureof CO_2(g) when 2 moles of CO_{} are added intoequilibirum mixture?(1) 4 atm(2) 2 atm(3) 6 atm(4) 5 atm
Answer» 12. In the equilibirum mixture CacO_{3(s)→}CaO(s) + CO,(g). Pressure ofCO_2(g) at 27^° C is 2 atm. What will be the pressureof CO_2(g) when 2 moles of CO_{} are added intoequilibirum mixture?(1) 4 atm(2) 2 atm(3) 6 atm(4) 5 atm

Discussion

2814.	An image formed by a pinhole camera is______and_______.
Answer» An image formed by a pinhole camera is______and_______.

Discussion

2815.	Is pith ball electroscope better than a gold leaf electroscope, if no why so?
Answer» Is pith ball electroscope better than a gold leaf electroscope, if no why so?

Discussion

2816.	Himalayan Quake 2005
Answer» Himalayan Quake 2005

Discussion

2817.	It is easier to swim in sea water than in river water. Explain the reason..... Pls try to answer fast and correctly..... Regards Mahima,
Answer» It is easier to swim in sea water than in river water. Explain the reason..... Pls try to answer fast and correctly..... Regards Mahima,

2817.

It is easier to swim in sea water than in river water. Explain the reason..... Pls try to answer fast and correctly..... Regards Mahima,

Answer»

It is easier to swim in sea water than in river water. Explain the reason.....

Pls try to answer fast and correctly.....

Regards Mahima,

Discussion

2818.	A pendulum makes 135 oscillations in a duration of 15 seconds. What is the time period of the pendulum?
Answer» A pendulum makes 135 oscillations in a duration of 15 seconds. What is the time period of the pendulum?

Discussion

2819.	56.If 1 kg of air(g=1.4) is heated adiabatically from zero degree celsius to 10 degree Celsius. then increase in its internal energy will be- (specific heat at constant volume = 0.172 Cal/gm.C )
Answer» 56.If 1 kg of air(g=1.4) is heated adiabatically from zero degree celsius to 10 degree Celsius. then increase in its internal energy will be- (specific heat at constant volume = 0.172 Cal/gm.C )

Discussion

2820.	Two charged thin infinite plane sheets of uniform surface charge density σ+ and σ−, where \|σ+\| > \|σ−\|, intersect at a right angle. Which of the following best represents the electric field lines for this system?
Answer» Two charged thin infinite plane sheets of uniform surface charge density $σ_{+}$ and $σ_{-}$ , where $\| σ_{+} \|$ > $\| σ_{-} \|$ , intersect at a right angle. Which of the following best represents the electric field lines for this system?

Discussion

2821.	Rajesh measures the length of a box to be 30 cm using a scale that has a broken left end. The actual length of the box is 29 cm. What is the zero error?1
Answer» Rajesh measures the length of a box to be $30 c m$ using a scale that has a broken left end. The actual length of the box is $29 c m$ . What is the zero error? 1

Discussion

2822.	A body of mass m is travelling with velocity v. How much work should be done on it to bring it to rest?
Answer» A body of mass m is travelling with velocity v. How much work should be done on it to bring it to rest?

Discussion

2823.	36. Why the kinetic energy remains the same even when the intensity of the electromagnetic radiation increases?
Answer» 36. Why the kinetic energy remains the same even when the intensity of the electromagnetic radiation increases?

Discussion

2824.	If contact forces (repulsion between atoms) does not exist then how friction is possible ?
Answer» If contact forces (repulsion between atoms) does not exist then how friction is possible ?

Discussion

2825.	What is the angle of incidence of a ray of light if the reflected ray is at an angle of 90∘ to the incidence ray?
Answer» What is the angle of incidence of a ray of light if the reflected ray is at an angle of $90^{\circ}$ to the incidence ray?

Discussion

2826.	The mass of an empty botttle is 30g, it is 75g when filled completely with water and 65g when filled completely with liquid. Find i.volume of density bottle ii. density of liquid. iii. relative density
Answer» The mass of an empty botttle is 30g, it is 75g when filled completely with water and 65g when filled completely with liquid. Find i.volume of density bottle ii. density of liquid. iii. relative density

Discussion

2827.	What are the various expansions that a solid undergoes?
Answer» What are the various expansions that a solid undergoes?

Discussion

2828.	How does liquid evaporates ?
Answer» How does liquid evaporates ?

2828.

How does liquid evaporates ?

Answer»

How does liquid evaporates ?

Discussion

2829.	99.Does spherical mirrors also show lateral inversion?why or why not?give reasons in brief
Answer» 99.Does spherical mirrors also show lateral inversion?why or why not?give reasons in brief

Discussion

2830.	Number of moles of Mn{0_4^-}_ required to oxidise 1 mol of Na_2S_2O_3 in faintly alkaline medium
Answer» Number of moles of Mn{0_4^-}_ required to oxidise 1 mol of Na_2S_2O_3 in faintly alkaline medium

Discussion

2831.	A particle moving in x-y plane has a velocity at time t= 8 s given by (6/+8j) m/s and at t= 8.2 s its velocitybecomes (6.6i+8.8j) m/s. The magnitude of its average acceleration during this interval of 0.2 s is
Answer» A particle moving in x-y plane has a velocity at time t= 8 s given by (6/+8j) m/s and at t= 8.2 s its velocity becomes (6.6i+8.8j) m/s. The magnitude of its average acceleration during this interval of 0.2 s is

Discussion

2832.	a particle moves a dis†an ce x in time t acording to the equation x=(t+3)^-^1 the acceleration of the particle is proportional to (a) (velocity)^{2/3} (b) (dis†an ce)^2 (c)dis†an ce (d)(velocity)^{3/2
Answer» a particle moves a dis†an ce x in time t acording to the equation x=(t+3)^-^1 the acceleration of the particle is proportional to (a) (velocity)^{2/3} (b) (dis†an ce)^2 (c)dis†an ce (d)(velocity)^{3/2

Discussion

2833.	41.What is acid?
Answer» 41.What is acid?

Discussion

2834.	What is a real image ? Name the mirror which can be used to obtain the real image of an object. What should be the position of the object relative to the mirror.
Answer» What is a real image ? Name the mirror which can be used to obtain the real image of an object. What should be the position of the object relative to the mirror.

Discussion

2835.	Describe the structure and function of reduction bodies in sponges in detail , with diagrams .
Answer» Describe the structure and function of reduction bodies in sponges in detail , with diagrams .

Discussion

2836.	If the cofficient of friction between the block of mass 5kg and wall is 0.5,then minimum force F required to hold the block with wall is take g=10
Answer» If the cofficient of friction between the block of mass 5kg and wall is 0.5,then minimum force F required to hold the block with wall is take g=10

Discussion

2837.	Ram is pushing a block from right with a constant force F. Rajat starts pushing from left with 0 force but keeps increasing his force uniformly. Anser the following giving reasons :(i) What is the direction of friction currently ?(ii) Will the direction of friction ever change ? [5 MARKS]
Answer» Ram is pushing a block from right with a constant force F. Rajat starts pushing from left with 0 force but keeps increasing his force uniformly. Anser the following giving reasons : (i) What is the direction of friction currently ? (ii) Will the direction of friction ever change ? [5 MARKS]

2837.

Ram is pushing a block from right with a constant force F. Rajat starts pushing from left with 0 force but keeps increasing his force uniformly. Anser the following giving reasons :(i) What is the direction of friction currently ?(ii) Will the direction of friction ever change ? [5 MARKS]

Answer»

Ram is pushing a block from right with a constant force F. Rajat starts pushing from left with 0 force but keeps increasing his force uniformly. Anser the following giving reasons :

(i) What is the direction of friction currently ?

(ii) Will the direction of friction ever change ? [5 MARKS]

Discussion

2838.	Based on the impact created, estimate the magnitude of earthquakes on Richter scale that occurred at Bhuj and Kashmir.
Answer» Based on the impact created, estimate the magnitude of earthquakes on Richter scale that occurred at Bhuj and Kashmir.

Discussion

2839.	Say if the statements given below are right or wrong. Rewrite the statements after correcting them.(a) Venus is the planet closest to the sun.(b) Mercury is called a stormy planet.(c) Jupiter is the biggest planet.
Answer» Say if the statements given below are right or wrong. Rewrite the statements after correcting them. (a) Venus is the planet closest to the sun. (b) Mercury is called a stormy planet. (c) Jupiter is the biggest planet.

Discussion

2840.	The intensity of sound from a source at a distance of 4 m is 2 × 10–8 W/m2. The intensity of sound at distance of 2 m from the source is
Answer» The intensity of sound from a source at a distance of 4 m is 2 × 10–8 W/m2. The intensity of sound at distance of 2 m from the source is

Discussion

2841.	The light ray parallel to principal axis of a convex mirror will:-
Answer» The light ray parallel to principal axis of a convex mirror will:-

2841.

The light ray parallel to principal axis of a convex mirror will:-

Answer»

The light ray parallel to principal axis of a convex mirror will:-

Discussion

2842.	What are ions?
Answer» What are ions?

Discussion

2843.	A person moves for 10 s with velocity 3 m/s then velocity 4 m/s for another 5 s and finally moves with velocity 5 m/s for 6 s. The average speed of the person will be
Answer» A person moves for 10 s with velocity 3 m/s then velocity 4 m/s for another 5 s and finally moves with velocity 5 m/s for 6 s. The average speed of the person will be

Discussion

2844.	The velocity of sound is 330 m/s and the time period of the sound wave is 0.1 s. Calculate the wavelength of the sound wave.
Answer» The velocity of sound is $330 m/s$ and the time period of the sound wave is $0.1 s$ . Calculate the wavelength of the sound wave.

Discussion

2845.	Water is poured in a steel container for heating. The level of water in the container after heating will ___.
Answer» Water is poured in a steel container for heating. The level of water in the container after heating will ___.

Discussion

2846.	50.Several electric bulbs designed to be used on a 220v electric supply line are rated at 10 w. How many lamps can be connected in parallel with each other across two wires of 220v line, if the maximum allowed current is 5A?
Answer» 50.Several electric bulbs designed to be used on a 220v electric supply line are rated at 10 w. How many lamps can be connected in parallel with each other across two wires of 220v line, if the maximum allowed current is 5A?

Discussion

2847.	Which of the following natural phenomena is not possible to predict?
Answer» Which of the following natural phenomena is not possible to predict?

Discussion

2848.	Describe some of the sounds you hear at night.
Answer» Describe some of the sounds you hear at night.

Discussion

2849.	Write a note on orbiter and lander of Chandrayaan – 2.
Answer» Write a note on orbiter and lander of Chandrayaan – 2.

Discussion

2850.	What will be electric flux through a hollow sphere
Answer» What will be electric flux through a hollow sphere

Discussion

Explore topic-wise InterviewSolutions in .

Two particles of equal mass m go around a circle of radius R under the action of their mutual gravitationaattraction. The speed of each particle with respect to their centre of mass is(1) GmGm4R(3)Gm3RarGm2R

A block of mass m is resting on a horizontal surface. The coefficient of friction is 0.4. A horizontal force of 10N is needed to move the block. Normal reaction N acting is

8.State true OR false and if true give reason and if false give reason (1) All dissymmetrical objects are optically active. (2) All asymmetrical objects are optically active.

Why kinetic energy of a system is not equal to 1/2 M total ×V^2com

A beaker contains water up to a height h1 and K.oil above water up to another height h2. Find the apparent shift in the position of the bottom of the beaker when viewed from above. Refractive index of water is μ1 and that of K.oil is μ2.

Pritish pulls a load up an inclined road. What is/are the force(s) he must overcome to pull it up?

Five charged particles each +Q and one –Q are placed at the six corners of a regular hexagon of sides length a. The electrostatic force over q0 placed at the centre is given by

Is angular acceleration of a particle moving along a circular path with uniform speed -- zero/variable ?

In an electric circuit 3 incandescent bulbs A B C of rating A( 40W ,200V) B(50W ,200V) C(100W,200V) are connected in series with a 200V supply what is the power dissipated across 50 watt bulb

Question 16 Boojho stands at A just on the side of a plane mirror as shown in Fig. 16.20. Can he see himself in the mirror? Also can he see the image of objects situated at P, Q and R?

State the parts of the rocket.

12. In the equilibirum mixture CacO_{3(s)→}CaO(s) + CO,(g). Pressure ofCO_2(g) at 27^° C is 2 atm. What will be the pressureof CO_2(g) when 2 moles of CO_{} are added intoequilibirum mixture?(1) 4 atm(2) 2 atm(3) 6 atm(4) 5 atm

An image formed by a pinhole camera is______and_______.

Is pith ball electroscope better than a gold leaf electroscope, if no why so?

Himalayan Quake 2005

It is easier to swim in sea water than in river water. Explain the reason..... Pls try to answer fast and correctly..... Regards Mahima,

A pendulum makes 135 oscillations in a duration of 15 seconds. What is the time period of the pendulum?

56.If 1 kg of air(g=1.4) is heated adiabatically from zero degree celsius to 10 degree Celsius. then increase in its internal energy will be- (specific heat at constant volume = 0.172 Cal/gm.C )

Two charged thin infinite plane sheets of uniform surface charge density σ+ and σ−, where |σ+| &gt; |σ−|, intersect at a right angle. Which of the following best represents the electric field lines for this system?

Rajesh measures the length of a box to be 30 cm using a scale that has a broken left end. The actual length of the box is 29 cm. What is the zero error?1

A body of mass m is travelling with velocity v. How much work should be done on it to bring it to rest?

36. Why the kinetic energy remains the same even when the intensity of the electromagnetic radiation increases?

If contact forces (repulsion between atoms) does not exist then how friction is possible ?

What is the angle of incidence of a ray of light if the reflected ray is at an angle of 90∘ to the incidence ray?

The mass of an empty botttle is 30g, it is 75g when filled completely with water and 65g when filled completely with liquid. Find i.volume of density bottle ii. density of liquid. iii. relative density

What are the various expansions that a solid undergoes?

How does liquid evaporates ? ​​​​​

99.Does spherical mirrors also show lateral inversion?why or why not?give reasons in brief

Number of moles of Mn{0_4^-}_ required to oxidise 1 mol of Na_2S_2O_3 in faintly alkaline medium

A particle moving in x-y plane has a velocity at time t= 8 s given by (6/+8j) m/s and at t= 8.2 s its velocitybecomes (6.6i+8.8j) m/s. The magnitude of its average acceleration during this interval of 0.2 s is

a particle moves a dis†an ce x in time t acording to the equation x=(t+3)^-^1 the acceleration of the particle is proportional to (a) (velocity)^{2/3} (b) (dis†an ce)^2 (c)dis†an ce (d)(velocity)^{3/2

41.What is acid?

What is a real image ? Name the mirror which can be used to obtain the real image of an object. What should be the position of the object relative to the mirror.

Describe the structure and function of reduction bodies in sponges in detail , with diagrams .

If the cofficient of friction between the block of mass 5kg and wall is 0.5,then minimum force F required to hold the block with wall is take g=10

Ram is pushing a block from right with a constant force F. Rajat starts pushing from left with 0 force but keeps increasing his force uniformly. Anser the following giving reasons :(i) What is the direction of friction currently ?(ii) Will the direction of friction ever change ? [5 MARKS]

Based on the impact created, estimate the magnitude of earthquakes on Richter scale that occurred at Bhuj and Kashmir.

Say if the statements given below are right or wrong. Rewrite the statements after correcting them.(a) Venus is the planet closest to the sun.(b) Mercury is called a stormy planet.(c) Jupiter is the biggest planet.

The intensity of sound from a source at a distance of 4 m is 2 × 10–8 W/m2. The intensity of sound at distance of 2 m from the source is

The light ray parallel to principal axis of a convex mirror will:-

What are ions?

A person moves for 10 s with velocity 3 m/s then velocity 4 m/s for another 5 s and finally moves with velocity 5 m/s for 6 s. The average speed of the person will be

The velocity of sound is 330 m/s and the time period of the sound wave is 0.1 s. Calculate the wavelength of the sound wave.

Water is poured in a steel container for heating. The level of water in the container after heating will ___.

50.Several electric bulbs designed to be used on a 220v electric supply line are rated at 10 w. How many lamps can be connected in parallel with each other across two wires of 220v line, if the maximum allowed current is 5A?

Which of the following natural phenomena is not possible to predict?

Describe some of the sounds you hear at night.

Write a note on orbiter and lander of Chandrayaan – 2.

What will be electric flux through a hollow sphere

An image formed by a pinhole camera isand_.

Two charged thin infinite plane sheets of uniform surface charge density σ+ and σ−, where |σ+| > |σ−|, intersect at a right angle. Which of the following best represents the electric field lines for this system?

How does liquid evaporates ?