16569 + Interview Questions in Physics

1.	In a cathode ray tube, the cathode plate is coated with oxide of barium or strontium because
Answer» In a cathode ray tube, the cathode plate is coated with oxide of barium or strontium because

Discussion

2.	Identify the part of the plant shown in the images below.
Answer» Identify the part of the plant shown in the images below.

Discussion

3.	What is the angle of deviation? Does it only occur in a prism or does any refracted light ray have an angle of deviation?
Answer» What is the angle of deviation? Does it only occur in a prism or does any refracted light ray have an angle of deviation?

Discussion

4.	An object is placed at 60 cm from the pole of a concave mirror, whose focal length is 20 cm? Find the distance at the which image is formed.
Answer» An object is placed at 60 cm from the pole of a concave mirror, whose focal length is 20 cm? Find the distance at the which image is formed.

Discussion

5.	A block is thrown upwards with a kinetic energy of 2 J. If the mass of the block is 100 g. Find its maximum height.
Answer» A block is thrown upwards with a kinetic energy of $2 J$ . If the mass of the block is $100 g$ . Find its maximum height.

Discussion

6.	Why lens maker formula(n-1)(1/R1-1/R2) valid for thin lens only. What will happen if we apply this formula in thick lens.
Answer» Why lens maker formula(n-1)(1/R1-1/R2) valid for thin lens only. What will happen if we apply this formula in thick lens.

Discussion

7.	The part of the petrol engine in which the petrol vapours mix with air is called ___ .
Answer» The part of the petrol engine in which the petrol vapours mix with air is called ___ .

Discussion

8.	A particle is projected vertically upward to reach maximum height H. Find the time at which ratio of potential and kinetic energy is 3:1
Answer» A particle is projected vertically upward to reach maximum height H. Find the time at which ratio of potential and kinetic energy is 3:1

Discussion

9.	In which of these applications are isotopes used? A. Uranium as fuel in nuclear reactors B. Iodine in the treatment of goitre C. Cobalt in the treatment of cancer D. Oxygen in the treatment of cancer
Answer» In which of these applications are isotopes used? A. Uranium as fuel in nuclear reactors B. Iodine in the treatment of goitre C. Cobalt in the treatment of cancer D. Oxygen in the treatment of cancer

Discussion

10.	The lens shown in fig. is made of two different materials. A point object is placed on the principal axis of this lens. How many images will be obtained?
Answer» The lens shown in fig. is made of two different materials. A point object is placed on the principal axis of this lens. How many images will be obtained?

10.

The lens shown in fig. is made of two different materials. A point object is placed on the principal axis of this lens. How many images will be obtained?

Answer»

The lens shown in fig. is made of two different materials. A point object is placed on the principal axis of this lens. How many images will be obtained?

Discussion

11.	19.Fundamental frequency of a sonometer wire is n. If the tension is made 3 times and length and diameter are also increased 3 times, what is the new frequency?
Answer» 19.Fundamental frequency of a sonometer wire is n. If the tension is made 3 times and length and diameter are also increased 3 times, what is the new frequency?

Discussion

12.	A ball of mass 0.20 kg is thrown vertically upwards with an initial velocity of 20 m s-1 Calculate the maximum potential energy it gains as it goes up.
Answer» A ball of mass 0.20 kg is thrown vertically upwards with an initial velocity of 20 m s^-1 Calculate the maximum potential energy it gains as it goes up.

Discussion

13.	The value of two resistors are R1=(6±0.3)kΩ and R2=(10±0.2)kΩ. The Percentage error in equivalent resistance when they are connected in parallel is 3.875 %or 10.125%?
Answer» The value of two resistors are R1=(6±0.3)kΩ and R2=(10±0.2)kΩ. The Percentage error in equivalent resistance when they are connected in parallel is 3.875 %or 10.125%?

Discussion

14.	why does the image of an object around a flame looks shaky(like a few centimetres around the flame)
Answer» why does the image of an object around a flame looks shaky(like a few centimetres around the flame)

Discussion

15.	To an astronaut, why does the sky appear dark instead of blue?
Answer» To an astronaut, why does the sky appear dark instead of blue?

Discussion

16.	An electron moving along a horizontal line with respect to observer and towards north. Due to earthmagnetic field it deflects touards east then postion of observer (1) In NHS (2) In SHS (3) At Equator 4) None
Answer» An electron moving along a horizontal line with respect to observer and towards north. Due to earthmagnetic field it deflects touards east then postion of observer (1) In NHS (2) In SHS (3) At Equator 4) None

Discussion

17.	Explain optical centre of a lens with the help of proper diagram(s).
Answer» Explain optical centre of a lens with the help of proper diagram(s).

Discussion

18.	Calculate the refractive index of the medium Y, when a light ray enters from air at an angle ∠i=45∘, and ∠r=30∘?0.7
Answer» Calculate the refractive index of the medium Y, when a light ray enters from air at an angle $∠ i = 45^{\circ}$ , and $∠ r = 30^{\circ}$ ? 0.7

18.

Calculate the refractive index of the medium Y, when a light ray enters from air at an angle ∠i=45∘, and ∠r=30∘?0.7

Answer» Calculate the refractive index of the medium Y, when a light ray enters from air at an angle

∠ i = 45^{\circ}

, and

∠ r = 30^{\circ}

?

0.7

Discussion

19.	An L−R circuit has L=1 H and R=2 Ω. It is connected across an emf of 2 V at t=0. Find the rate of change of current in the circuit at t=100 ms. (e1/5=1.22)
Answer» An $L - R$ circuit has $L = 1 H$ and $R = 2 Ω$ . It is connected across an emf of $2 V$ at $t = 0$ . Find the rate of change of current in the circuit at $t = 100 ms .$ $(e^{1 / 5} = 1.22)$

Discussion

20.	3.The velocities of A and B are shown in Figure. Find the (speed in m/s) of block C (Assume that the pulleys and string are ideal
Answer» 3.The velocities of A and B are shown in Figure. Find the (speed in m/s) of block C (Assume that the pulleys and string are ideal

Discussion

21.	Question 13 (c) A coil of insulated copper wire is connected to a galvanometer. What will happen if a bar magnet is (iii) held stationary inside the coil?
Answer» Question 13 (c) A coil of insulated copper wire is connected to a galvanometer. What will happen if a bar magnet is (iii) held stationary inside the coil?

Discussion

22.	What is the mirror image of b3k4s
Answer» What is the mirror image of b3k4s

Discussion

23.	The near point of a hypermetropic eye is 1 metre What is the power of the lens required to correct this defect? (Assuming that the near point of a normal eye as 25cm)
Answer» The near point of a hypermetropic eye is 1 metre What is the power of the lens required to correct this defect? (Assuming that the near point of a normal eye as 25cm)

Discussion

24.	37. Light rays from a very small object emersed in water falls on bubble of radius . R . Assume object is very close to surface of bubble. Refractive index of water is 4/3. Use following formula and see the figure to find what type of image is formed and at what distance from centre of bubble?
Answer» 37. Light rays from a very small object emersed in water falls on bubble of radius . R . Assume object is very close to surface of bubble. Refractive index of water is 4/3. Use following formula and see the figure to find what type of image is formed and at what distance from centre of bubble?

Discussion

25.	A machine gun has a mass 5 kg. It fires bullets ofmass 50 g each at the rate of 30 bullets/minute witha speed of 400 m/s. Force required to hold the gunin position isnmy30X5(1) 150 N(2) 15 N(3) 10N14) 20 N
Answer» A machine gun has a mass 5 kg. It fires bullets ofmass 50 g each at the rate of 30 bullets/minute witha speed of 400 m/s. Force required to hold the gunin position isnmy30X5(1) 150 N(2) 15 N(3) 10N14) 20 N

Discussion

26.	Where is the focal length of the eye located is is on the retina?
Answer» Where is the focal length of the eye located is is on the retina?

Discussion

27.	Determine the heat energy generated in terms of kJ in an induction stove when a current of 8 A passes through its coils for 5 min when applied voltage is 230 V.
Answer» Determine the heat energy generated in terms of kJ in an induction stove when a current of 8 A passes through its coils for 5 min when applied voltage is 230 V.

Discussion

28.	What is magnification in the below diagram? If OA = 10 cm and O’A’ = 2 cm?
Answer» What is magnification in the below diagram? If OA = 10 cm and O’A’ = 2 cm?

28.

What is magnification in the below diagram? If OA = 10 cm and O’A’ = 2 cm?

Answer»

What is magnification in the below diagram?

If OA = 10 cm and O’A’ = 2 cm?

Discussion

29.	What happens in the fuse which melts it to break the electrical circuit?
Answer» What happens in the fuse which melts it to break the electrical circuit?

Discussion

30.	A person brings a mass of 2 kg from A to B. The increase in kinetic energy of the mass is 4 J and the work done by the person on the mass is -10 J. The gravitational potential difference between B and A is (i.e., VB−VA)
Answer» A person brings a mass of 2 kg from A to B. The increase in kinetic energy of the mass is 4 J and the work done by the person on the mass is -10 J. The gravitational potential difference between B and A is (i.e., $V_{B} - V_{A}$ )

Discussion

31.	Name the physical quantity which is measured in (i) kW, (ii) kWh and (iii) Wh.
Answer» Name the physical quantity which is measured in (i) kW, (ii) kWh and (iii) Wh.

Discussion

32.	An electric heater of resistance 8 ohms draws 15 A from the service mains for 2 hours. Calculate the rate at which heat is developed in the heater. (Give your answer in Js)
Answer» An electric heater of resistance 8 ohms draws 15 A from the service mains for 2 hours. Calculate the rate at which heat is developed in the heater. (Give your answer in $\frac{J}{s}$ )

Discussion

33.	The power of accommodation of normal vision is about
Answer» The power of accommodation of normal vision is about

Discussion

34.	Current flow through a resistor R reduced uniformly to zero in the time interval T.If charge flow through the resistor R in this time is Q,find the total amount of heat produced through the resistor in this time interval T
Answer» Current flow through a resistor R reduced uniformly to zero in the time interval T.If charge flow through the resistor R in this time is Q,find the total amount of heat produced through the resistor in this time interval T

Discussion

35.	In a prism, why does the angle of deviation increase as the angle of prism increases?
Answer» In a prism, why does the angle of deviation increase as the angle of prism increases?

Discussion

36.	When 92U235 undergoes fission, 0.1% of its original mass is changed into energy.9×10xJ of energy is released if 1 kg of 92U235 undergoes fission, then the value of x___
Answer» When $_{92} U^{235}$ undergoes fission, 0.1% of its original mass is changed into energy. $9 \times 10^{x} J$ of energy is released if $1 k g$ of $_{92} U^{235}$ undergoes fission, then the value of $x$ ___

Discussion

37.	The moment of a force about a given axis depends:
Answer» The moment of a force about a given axis depends:

Discussion

38.	A train of mass M is moving on a circular track of radius R with cons†an t speed v.The lenght of the train is half of the perimeter of the track.Find the linear momentum of the train.
Answer» A train of mass M is moving on a circular track of radius R with cons†an t speed v.The lenght of the train is half of the perimeter of the track.Find the linear momentum of the train.

Discussion

39.	In the circuit shown , the resistance of voltmeter is 10,000 Ω and that of ammeter is 20 Ω. The ammeter reading is 0.10 A and voltmeter reading is 12 V. Then value of R is equal to
Answer» In the circuit shown , the resistance of voltmeter is $10, 000 Ω$ and that of ammeter is $20 Ω$ . The ammeter reading is $0.10 A$ and voltmeter reading is $12 V$ . Then value of $R$ is equal to

Discussion

40.	What is the current (I) in the circuit?
Answer» What is the current (I) in the circuit?

Discussion

41.	If ve and vo represent the escape velocity and orbital velocity of a satellite corresponding to a circular orbit of radius R, then
Answer» If $v_{e}$ and $v_{o}$ represent the escape velocity and orbital velocity of a satellite corresponding to a circular orbit of radius R, then

Discussion

42.	Due to a point isotropic sonic source, loudness at a point is L=60 dB. If density of air is ρ=(15/11) kg/m3 and velocity of sound in air is v=330 m/s, the pressure oscillation amplitude at the point of observation is: [I0=10−12 W/m2]
Answer» Due to a point isotropic sonic source, loudness at a point is $L = 60 dB$ . If density of air is $ρ = (15 / 11) {kg/m}^{3}$ and velocity of sound in air is $v = 330 m/s$ , the pressure oscillation amplitude at the point of observation is: $[I_{0} = 10^{- 12} {W/m}^{2}]$

Discussion

43.	Position vector of a point charge 3.7 μC with respect to origin is (1^i+2^j+3^k) m. The potential due to point charge at origin is
Answer» Position vector of a point charge $3.7 μ C$ with respect to origin is $(1^i + 2^j + 3^k) m$ . The potential due to point charge at origin is

Discussion

44.	State whether the following statement is true or false : A student says that we can see an object because light from our eyes is reflected back by the object.
Answer» State whether the following statement is true or false : A student says that we can see an object because light from our eyes is reflected back by the object.

Discussion

45.	What is the speed of light in air?
Answer» What is the speed of light in air?

Discussion

46.	A 1 kW heater is used for an hour. The energy consumed is
Answer» A 1 kW heater is used for an hour. The energy consumed is

Discussion

47.	Focal length of the convex lens shown in the figure is 20 cm. Find the position of the image and magnitude of image velocity, when the object is at a distance of 30 cm from the pole.
Answer» Focal length of the convex lens shown in the figure is $20 cm$ . Find the position of the image and magnitude of image velocity, when the object is at a distance of $30 cm$ from the pole.

Discussion

48.	The effective resistance across the points x and y is-
Answer» The effective resistance across the points $x$ and $y$ is-

Discussion

49.	Question 27In a village in Karnataka, people started cultivating crops all around a lake which was always filled with water. They added fertilisers to their field in order to enhance the yield. Soon they discovered that the waterbody was completely covered with green floating plants and fishes started dying in large numbers.Analyze the situation and give reasons for excessive growth of plants and death of fish in the lake.
Answer» Question 27 In a village in Karnataka, people started cultivating crops all around a lake which was always filled with water. They added fertilisers to their field in order to enhance the yield. Soon they discovered that the waterbody was completely covered with green floating plants and fishes started dying in large numbers. Analyze the situation and give reasons for excessive growth of plants and death of fish in the lake.

Discussion

50.	Which type of lens is required to correct Hypermetropia defect?
Answer» Which type of lens is required to correct Hypermetropia defect?

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

In a cathode ray tube, the cathode plate is coated with oxide of barium or strontium because

Identify the part of the plant shown in the images below.

What is the angle of deviation? Does it only occur in a prism or does any refracted light ray have an angle of deviation?

An object is placed at 60 cm from the pole of a concave mirror, whose focal length is 20 cm? Find the distance at the which image is formed.

A block is thrown upwards with a kinetic energy of 2 J. If the mass of the block is 100 g. Find its maximum height.

Why lens maker formula(n-1)(1/R1-1/R2) valid for thin lens only. What will happen if we apply this formula in thick lens.

The part of the petrol engine in which the petrol vapours mix with air is called ___ .

A particle is projected vertically upward to reach maximum height H. Find the time at which ratio of potential and kinetic energy is 3:1

In which of these applications are isotopes used? A. Uranium as fuel in nuclear reactors B. Iodine in the treatment of goitre C. Cobalt in the treatment of cancer D. Oxygen in the treatment of cancer

The lens shown in fig. is made of two different materials. A point object is placed on the principal axis of this lens. How many images will be obtained?

19.Fundamental frequency of a sonometer wire is n. If the tension is made 3 times and length and diameter are also increased 3 times, what is the new frequency?

A ball of mass 0.20 kg is thrown vertically upwards with an initial velocity of 20 m s-1 Calculate the maximum potential energy it gains as it goes up.

The value of two resistors are R1=(6±0.3)kΩ and R2=(10±0.2)kΩ. The Percentage error in equivalent resistance when they are connected in parallel is 3.875 %or 10.125%?

why does the image of an object around a flame looks shaky(like a few centimetres around the flame)

To an astronaut, why does the sky appear dark instead of blue?

An electron moving along a horizontal line with respect to observer and towards north. Due to earthmagnetic field it deflects touards east then postion of observer (1) In NHS (2) In SHS (3) At Equator 4) None

Explain optical centre of a lens with the help of proper diagram(s).

Calculate the refractive index of the medium Y, when a light ray enters from air at an angle ∠i=45∘, and ∠r=30∘?0.7

An L−R circuit has L=1 H and R=2 Ω. It is connected across an emf of 2 V at t=0. Find the rate of change of current in the circuit at t=100 ms. (e1/5=1.22)

3.The velocities of A and B are shown in Figure. Find the (speed in m/s) of block C (Assume that the pulleys and string are ideal

Question 13 (c) A coil of insulated copper wire is connected to a galvanometer. What will happen if a bar magnet is (iii) held stationary inside the coil?

What is the mirror image of b3k4s

The near point of a hypermetropic eye is 1 metre What is the power of the lens required to correct this defect? (Assuming that the near point of a normal eye as 25cm)

37. Light rays from a very small object emersed in water falls on bubble of radius . R . Assume object is very close to surface of bubble. Refractive index of water is 4/3. Use following formula and see the figure to find what type of image is formed and at what distance from centre of bubble?

A machine gun has a mass 5 kg. It fires bullets ofmass 50 g each at the rate of 30 bullets/minute witha speed of 400 m/s. Force required to hold the gunin position isnmy30X5(1) 150 N(2) 15 N(3) 10N14) 20 N

Where is the focal length of the eye located is is on the retina?

Determine the heat energy generated in terms of kJ in an induction stove when a current of 8 A passes through its coils for 5 min when applied voltage is 230 V.

What is magnification in the below diagram? If OA = 10 cm and O’A’ = 2 cm?

What happens in the fuse which melts it to break the electrical circuit?

A person brings a mass of 2 kg from A to B. The increase in kinetic energy of the mass is 4 J and the work done by the person on the mass is -10 J. The gravitational potential difference between B and A is (i.e., VB−VA)

Name the physical quantity which is measured in (i) kW, (ii) kWh and (iii) Wh.

An electric heater of resistance 8 ohms draws 15 A from the service mains for 2 hours. Calculate the rate at which heat is developed in the heater. (Give your answer in Js)

The power of accommodation of normal vision is about

Current flow through a resistor R reduced uniformly to zero in the time interval T.If charge flow through the resistor R in this time is Q,find the total amount of heat produced through the resistor in this time interval T

In a prism, why does the angle of deviation increase as the angle of prism increases?

When 92U235 undergoes fission, 0.1% of its original mass is changed into energy.9×10xJ of energy is released if 1 kg of 92U235 undergoes fission, then the value of x___

The moment of a force about a given axis depends:

A train of mass M is moving on a circular track of radius R with cons†an t speed v.The lenght of the train is half of the perimeter of the track.Find the linear momentum of the train.

In the circuit shown , the resistance of voltmeter is 10,000 Ω and that of ammeter is 20 Ω. The ammeter reading is 0.10 A and voltmeter reading is 12 V. Then value of R is equal to

What is the current (I) in the circuit?

If ve and vo represent the escape velocity and orbital velocity of a satellite corresponding to a circular orbit of radius R, then

Due to a point isotropic sonic source, loudness at a point is L=60 dB. If density of air is ρ=(15/11) kg/m3 and velocity of sound in air is v=330 m/s, the pressure oscillation amplitude at the point of observation is: [I0=10−12 W/m2]

Position vector of a point charge 3.7 μC with respect to origin is (1^i+2^j+3^k) m. The potential due to point charge at origin is

State whether the following statement is true or false : A student says that we can see an object because light from our eyes is reflected back by the object.

What is the speed of light in air?

A 1 kW heater is used for an hour. The energy consumed is

Focal length of the convex lens shown in the figure is 20 cm. Find the position of the image and magnitude of image velocity, when the object is at a distance of 30 cm from the pole.

The effective resistance across the points x and y is-

Which type of lens is required to correct Hypermetropia defect?