16569 + Interview Questions in Physics

1.	For a single fixed pulley, an effort of 400N is required for a load of 300N. If the effort is moved by 30cm then calculate the efficiency of the pulley & energy that is used in overcoming friction.
Answer» For a single fixed pulley, an effort of 400N is required for a load of 300N. If the effort is moved by 30cm then calculate the efficiency of the pulley & energy that is used in overcoming friction.

Discussion

2.	What is meant by the gravitational potential energy ? Derive an expression for it for a body placed at a height above the ground.
Answer» What is meant by the gravitational potential energy ? Derive an expression for it for a body placed at a height above the ground.

Discussion

3.	A student focuses the image of a candle flame on a white screen using a convex lens. He noted down the position of the candle screen and the lens as shown below Position of candle = 12.0 cm Position of convex lens = 50.0 cm Position of the screen = 88.0 cm (i) What is the focal length of the convex lens? (ii) Where will the image be formed if he shifts the candle towards the lens at a position of 31.0 cm? (iii) What will be the nature of the image formed if he further shifts the candle towards the lens? (iv) Draw a ray diagram to show the formation of the image in case (iii) as said above.
Answer» A student focuses the image of a candle flame on a white screen using a convex lens. He noted down the position of the candle screen and the lens as shown below Position of candle = 12.0 cm Position of convex lens = 50.0 cm Position of the screen = 88.0 cm (i) What is the focal length of the convex lens? (ii) Where will the image be formed if he shifts the candle towards the lens at a position of 31.0 cm? (iii) What will be the nature of the image formed if he further shifts the candle towards the lens? (iv) Draw a ray diagram to show the formation of the image in case (iii) as said above.

Discussion

4.	What is dark energy
Answer» What is dark energy

Discussion

5.	Does refraction of light occur in translucent object
Answer» Does refraction of light occur in translucent object

Discussion

6.	A switch must be connected in the : (a) live wire (b) neutral wire (c) earth wire (d) either earth or neutral wire.
Answer» A switch must be connected in the : (a) live wire (b) neutral wire (c) earth wire (d) either earth or neutral wire.

6.

A switch must be connected in the : (a) live wire (b) neutral wire (c) earth wire (d) either earth or neutral wire.

Answer»

A switch must be connected in the :

(a) live wire

(b) neutral wire

(c) earth wire

(d) either earth or neutral wire.

Discussion

7.	What will happen when sound is focussed to a particular area?
Answer» What will happen when sound is focussed to a particular area?

Discussion

8.	You are given 3 bulbs of 40W, 60W and 100 W. Which of them has lower resistance, why
Answer» You are given 3 bulbs of 40W, 60W and 100 W. Which of them has lower resistance, why

Discussion

9.	Find the centre of gravity of a triangular disc:
Answer» Find the centre of gravity of a triangular disc:

Discussion

10.	Why an object which is positive is considered to have more potential while in object which is negative is considered to be of lower potential ? Is this for a the size of a Proton or its value of charge ?
Answer» Why an object which is positive is considered to have more potential while in object which is negative is considered to be of lower potential ? Is this for a the size of a Proton or its value of charge ?

Discussion

11.	The filament of a lamp is 80 cm from a screen and a converging lens forms an image of it on a screen, magnified three times. Find the distance of the lens from the filament and the focal length of the lens.
Answer» The filament of a lamp is 80 cm from a screen and a converging lens forms an image of it on a screen, magnified three times. Find the distance of the lens from the filament and the focal length of the lens.

Discussion

12.	Question 14 An object 5.0 cm in length is placed at a distance of 20 cm in front of a convex mirror of radius of curvature 30 cm. Find the position of the image, its nature and size.
Answer» Question 14 An object 5.0 cm in length is placed at a distance of 20 cm in front of a convex mirror of radius of curvature 30 cm. Find the position of the image, its nature and size.

Discussion

13.	When the two identical bulbs are connected in parallel they glow with same brightness there as when they are connected in series they again Glow with Same brightness explain
Answer» When the two identical bulbs are connected in parallel they glow with same brightness there as when they are connected in series they again Glow with Same brightness explain

Discussion

14.	→ 42He+ 20882B
Answer» $_{\to}_{2}^{4} H e +_{82}^{208} B$

Discussion

15.	Which of the following optical phenomenon is used in cinematography or movie projectors?
Answer» Which of the following optical phenomenon is used in cinematography or movie projectors?

Discussion

16.	A crow bar is a lever of_________.
Answer» A crow bar is a lever of_________.

Discussion

17.	A ray of light is incident at an angle of 45∘ on a square slab of a transparent material. What should be the refractive index of the material of the slab so that total internal reflection occurs at the vertical face AB?
Answer» A ray of light is incident at an angle of $45^{\circ}$ on a square slab of a transparent material. What should be the refractive index of the material of the slab so that total internal reflection occurs at the vertical face AB?

Discussion

18.	Find θ if the light is falling on the pole?
Answer» Find $θ$ if the light is falling on the pole?

18.

Find θ if the light is falling on the pole?

Answer»

Find $θ$ if the light is falling on the pole?

Discussion

19.	The diagram below shows a ray of white light PQ coming from an object P and incident on the surface of a thick glass plane mirror How many images will be formed and which image will be the brightest image.
Answer» The diagram below shows a ray of white light PQ coming from an object P and incident on the surface of a thick glass plane mirror How many images will be formed and which image will be the brightest image.

19.

The diagram below shows a ray of white light PQ coming from an object P and incident on the surface of a thick glass plane mirror How many images will be formed and which image will be the brightest image.

Answer»

The diagram below shows a ray of white light PQ coming from an object P and incident on the surface of a thick glass plane mirror

How many images will be formed and which image will be the brightest image.

Discussion

20.	A ray of light travelling from denser to rarer medium gets reflected back to the denser medium. This phenomenon is called as:
Answer» A ray of light travelling from denser to rarer medium gets reflected back to the denser medium. This phenomenon is called as:

Discussion

21.	Why do electrons flow in an opposite direction than the direction of current?
Answer» Why do electrons flow in an opposite direction than the direction of current?

Discussion

22.	The resultant of two forces acting on a body is zero if the forces are:
Answer» The resultant of two forces acting on a body is zero if the forces are:

Discussion

23.	When an electric current flows through a conductor it becomes hot. Why ? List the factor on which the heat produced in a conductor depends. State Joule's law of heating. How will the heat produced in an electric circuit be affected, if the resistance in the circuit is doubled for the same current ?
Answer» When an electric current flows through a conductor it becomes hot. Why ? List the factor on which the heat produced in a conductor depends. State Joule's law of heating. How will the heat produced in an electric circuit be affected, if the resistance in the circuit is doubled for the same current ?

Discussion

24.	Speed of the sound ___ with increase in the temperature.
Answer» Speed of the sound ___ with increase in the temperature.

Discussion

25.	An athlete can take a longer jump if he comes running from a distance. Identify the type of inertia.
Answer» An athlete can take a longer jump if he comes running from a distance. Identify the type of inertia.

Discussion

26.	A person needs a lens of power –5.5 dioptres for correcting distant vision, for correcting his near vision he needs a lens of power +1.5 dioptre. What is the focal length of the lens required and lens type required for correcting 1. distant vision, 2. near vision. [3 MARKS]
Answer» A person needs a lens of power –5.5 dioptres for correcting distant vision, for correcting his near vision he needs a lens of power +1.5 dioptre. What is the focal length of the lens required and lens type required for correcting 1. distant vision, 2. near vision. [3 MARKS]

Discussion

27.	If the length of a copper wire is increased by 5% due to stretching. What will be the percentage increase in its resistance?
Answer» If the length of a copper wire is increased by $5 %$ due to stretching. What will be the percentage increase in its resistance?

Discussion

28.	Myopia is characterised by:
Answer» Myopia is characterised by:

Discussion

29.	In the dispersion of light through a glass prism, which colour has the maximum deviation? [1 MARK]
Answer» In the dispersion of light through a glass prism, which colour has the maximum deviation? [1 MARK]

Discussion

30.	An object is 2 m from a lens which forms an erect image one-fourth (exactly) the size of the object. Determine the focal length of the lens. What type of lens is this ?
Answer» An object is 2 m from a lens which forms an erect image one-fourth (exactly) the size of the object. Determine the focal length of the lens. What type of lens is this ?

Discussion

31.	State three factors which affect the loundess of a sound heard by a listener.
Answer» State three factors which affect the loundess of a sound heard by a listener.

Discussion

32.	Atmospheric refraction causes advance sunrise and delayed sunset. By how much time is : (a) sunrise advanced ? (b) sunset delayed ?
Answer» Atmospheric refraction causes advance sunrise and delayed sunset. By how much time is : (a) sunrise advanced ? (b) sunset delayed ?

Discussion

33.	Question 15 In an electrical circuit two resistors of 2 Ω and 4 Ω respectively are connected in series to a 6 V battery. The heat dissipated by the 4 Ω resistor in 5 s will be (a) 5 J (b) 10 J (c) 20 J (d) 30 J
Answer» Question 15 In an electrical circuit two resistors of 2 $Ω$ and 4 $Ω$ respectively are connected in series to a 6 V battery. The heat dissipated by the 4 $Ω$ resistor in 5 s will be (a) 5 J (b) 10 J (c) 20 J (d) 30 J

Discussion

34.	Explain the concept of transformers
Answer» Explain the concept of transformers

Discussion

35.	Calculate the resistance of an aluminum cable of length 10km and diameter 2.0mm if the resistivity is 2.7x10-8 Ohm-meter
Answer» Calculate the resistance of an aluminum cable of length 10km and diameter 2.0mm if the resistivity is 2.7x10^-8 Ohm-meter

Discussion

36.	A single fixed pulley is used because it : (a) ha sthe mechanical advantage greater than 1 (b) has the velocity ratio less than 1 (c) gives 100% efficiency (d) helps to apply the effort in a convenient direction.
Answer» A single fixed pulley is used because it : (a) ha sthe mechanical advantage greater than 1 (b) has the velocity ratio less than 1 (c) gives $100 %$ efficiency (d) helps to apply the effort in a convenient direction.

36.

A single fixed pulley is used because it : (a) ha sthe mechanical advantage greater than 1 (b) has the velocity ratio less than 1 (c) gives 100% efficiency (d) helps to apply the effort in a convenient direction.

Answer»

A single fixed pulley is used because it :

(a) ha sthe mechanical advantage greater than 1

(b) has the velocity ratio less than 1

(c) gives $100 %$ efficiency

(d) helps to apply the effort in a convenient direction.

Discussion

37.	What is the reason behind quick rise in temperature of sand compared to sea?
Answer» What is the reason behind quick rise in temperature of sand compared to sea?

Discussion

38.	How atoms are existing
Answer» How atoms are existing

Discussion

39.	Name two fossil fuels.
Answer» Name two fossil fuels.

Discussion

40.	"Mass can neither be created nor be destroyed" but why and how is mass lost in nuclear energy ?
Answer» "Mass can neither be created nor be destroyed" but why and how is mass lost in nuclear energy ?

Discussion

41.	Which of the following is not an application of cryogenics?
Answer» Which of the following is not an application of cryogenics?

Discussion

42.	When an object is kept at any distance in front of a concave lens, the image formed is always : (a) virtual, erect and magnified (b) virtual, inverted and diminished. (c) virtual, erect and diminished (d) virtual, erect and same size as object
Answer» When an object is kept at any distance in front of a concave lens, the image formed is always : (a) virtual, erect and magnified (b) virtual, inverted and diminished. (c) virtual, erect and diminished (d) virtual, erect and same size as object

Discussion

43.	If an observer is walking away from the plane mirror with 6 m / sec. Then the velocity of the image with respect to observer will be
Answer» If an observer is walking away from the plane mirror with 6 m / sec. Then the velocity of the image with respect to observer will be

Discussion

44.	"As the electrons move relative to protons (ions) there is a relativistic charge per unit volume difference between the positive and the negative charges. This causes any external charges to feel a force we know as the magnetic field." Please Explain this sentence......
Answer» "As the electrons move relative to protons (ions) there is a relativistic charge per unit volume difference between the positive and the negative charges. This causes any external charges to feel a force we know as the magnetic field." Please Explain this sentence......

44.

"As the electrons move relative to protons (ions) there is a relativistic charge per unit volume difference between the positive and the negative charges. This causes any external charges to feel a force we know as the magnetic field." Please Explain this sentence......

Answer»

"As the electrons move relative to protons (ions) there is a relativistic charge per unit volume difference between the positive and the negative charges. This causes any external charges to feel a force we know as the magnetic field."

Please Explain this sentence......

Discussion

45.	Question 2 The magnetic field in a given region is uniform. Draw a diagram to represent it.
Answer» Question 2 The magnetic field in a given region is uniform. Draw a diagram to represent it.

Discussion

46.	In a step up transformer, the ratio of turns of primary to secondary is 1:10 and the primary voltage is 230 V. If the load current is 2 A, then the current in the primary is
Answer» In a step up transformer, the ratio of turns of primary to secondary is 1:10 and the primary voltage is 230 V. If the load current is 2 A, then the current in the primary is

Discussion

47.	The subjective property of light and sound which depends on the wavelength are:
Answer» The subjective property of light and sound which depends on the wavelength are:

Discussion

48.	If you are given two containers with 20 and 10 liters of water, you could achieve equilibrium by taking the __ amount of total water and pouring into both the containers.
Answer» If you are given two containers with 20 and 10 liters of water, you could achieve equilibrium by taking the __ amount of total water and pouring into both the containers.

Discussion

49.	What refractive index?
Answer» What refractive index?

Discussion

50.	At which of the following locations, the value of acceleration due to gravity is largest?
Answer» At which of the following locations, the value of acceleration due to gravity is largest?

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

For a single fixed pulley, an effort of 400N is required for a load of 300N. If the effort is moved by 30cm then calculate the efficiency of the pulley &amp; energy that is used in overcoming friction.

What is meant by the gravitational potential energy ? Derive an expression for it for a body placed at a height above the ground.

What is dark energy

Does refraction of light occur in translucent object

A switch must be connected in the : (a) live wire (b) neutral wire (c) earth wire (d) either earth or neutral wire.

What will happen when sound is focussed to a particular area?

You are given 3 bulbs of 40W, 60W and 100 W. Which of them has lower resistance, why

Find the centre of gravity of a triangular disc:

Why an object which is positive is considered to have more potential while in object which is negative is considered to be of lower potential ? Is this for a the size of a Proton or its value of charge ?

The filament of a lamp is 80 cm from a screen and a converging lens forms an image of it on a screen, magnified three times. Find the distance of the lens from the filament and the focal length of the lens.

Question 14 An object 5.0 cm in length is placed at a distance of 20 cm in front of a convex mirror of radius of curvature 30 cm. Find the position of the image, its nature and size.

When the two identical bulbs are connected in parallel they glow with same brightness there as when they are connected in series they again Glow with Same brightness explain

→ 42He+ 20882B

Which of the following optical phenomenon is used in cinematography or movie projectors?

A crow bar is a lever of_________.

A ray of light is incident at an angle of 45∘ on a square slab of a transparent material. What should be the refractive index of the material of the slab so that total internal reflection occurs at the vertical face AB?

Find θ if the light is falling on the pole?

The diagram below shows a ray of white light PQ coming from an object P and incident on the surface of a thick glass plane mirror How many images will be formed and which image will be the brightest image.

A ray of light travelling from denser to rarer medium gets reflected back to the denser medium. This phenomenon is called as:

Why do electrons flow in an opposite direction than the direction of current?

The resultant of two forces acting on a body is zero if the forces are:

When an electric current flows through a conductor it becomes hot. Why ? List the factor on which the heat produced in a conductor depends. State Joule's law of heating. How will the heat produced in an electric circuit be affected, if the resistance in the circuit is doubled for the same current ?

Speed of the sound ___ with increase in the temperature.

An athlete can take a longer jump if he comes running from a distance. Identify the type of inertia.

A person needs a lens of power –5.5 dioptres for correcting distant vision, for correcting his near vision he needs a lens of power +1.5 dioptre. What is the focal length of the lens required and lens type required for correcting 1. distant vision, 2. near vision. [3 MARKS]

If the length of a copper wire is increased by 5% due to stretching. What will be the percentage increase in its resistance?

Myopia is characterised by:

In the dispersion of light through a glass prism, which colour has the maximum deviation? [1 MARK]

An object is 2 m from a lens which forms an erect image one-fourth (exactly) the size of the object. Determine the focal length of the lens. What type of lens is this ?

State three factors which affect the loundess of a sound heard by a listener.

Atmospheric refraction causes advance sunrise and delayed sunset. By how much time is : (a) sunrise advanced ? (b) sunset delayed ?

Question 15 In an electrical circuit two resistors of 2 Ω and 4 Ω respectively are connected in series to a 6 V battery. The heat dissipated by the 4 Ω resistor in 5 s will be (a) 5 J (b) 10 J (c) 20 J (d) 30 J

Explain the concept of transformers

Calculate the resistance of an aluminum cable of length 10km and diameter 2.0mm if the resistivity is 2.7x10-8 Ohm-meter

A single fixed pulley is used because it : (a) ha sthe mechanical advantage greater than 1 (b) has the velocity ratio less than 1 (c) gives 100% efficiency (d) helps to apply the effort in a convenient direction.

What is the reason behind quick rise in temperature of sand compared to sea?

How atoms are existing

Name two fossil fuels.

"Mass can neither be created nor be destroyed" but why and how is mass lost in nuclear energy ?

Which of the following is not an application of cryogenics?

When an object is kept at any distance in front of a concave lens, the image formed is always : (a) virtual, erect and magnified (b) virtual, inverted and diminished. (c) virtual, erect and diminished (d) virtual, erect and same size as object

If an observer is walking away from the plane mirror with 6 m / sec. Then the velocity of the image with respect to observer will be

"As the electrons move relative to protons (ions) there is a relativistic charge per unit volume difference between the positive and the negative charges. This causes any external charges to feel a force we know as the magnetic field." Please Explain this sentence......

Question 2 The magnetic field in a given region is uniform. Draw a diagram to represent it.

In a step up transformer, the ratio of turns of primary to secondary is 1:10 and the primary voltage is 230 V. If the load current is 2 A, then the current in the primary is

The subjective property of light and sound which depends on the wavelength are:

If you are given two containers with 20 and 10 liters of water, you could achieve equilibrium by taking the __ amount of total water and pouring into both the containers.

What refractive index?

At which of the following locations, the value of acceleration due to gravity is largest?

For a single fixed pulley, an effort of 400N is required for a load of 300N. If the effort is moved by 30cm then calculate the efficiency of the pulley & energy that is used in overcoming friction.