16569 + Interview Questions in Physics

1.	A body of mass 25 kg is dragged on a horizontal rough road with a constant speed of 20 km/hr. If the coefficient of friction is 0.5, find the heat generated in one hour. If 50% of the heat is absorbed by the body, find the rise in temperature. Specific heat of the material of the body is 0.1 cal.gm−1(∘C)−1.
Answer» A body of mass 25 kg is dragged on a horizontal rough road with a constant speed of 20 km/hr. If the coefficient of friction is 0.5, find the heat generated in one hour. If $50 %$ of the heat is absorbed by the body, find the rise in temperature. Specific heat of the material of the body is $0.1 c a l . g m^{- 1} (^{\circ} C)^{- 1}$ .

Discussion

2.	The flow of which of the following fundamental particles leads to the existence of electricity?
Answer» The flow of which of the following fundamental particles leads to the existence of electricity?

Discussion

3.	Calculate the amount of ice which is required to cool 150 g of water contained in a vessel of mass 100 g at 30°C, such that the final temperature of the mixture is 5oC. Take specific heat capacity of material of vessel as 0.4 J g-1 oC-1 ; specific latent heat of fusion of ice = 336 J g-1 ; specific heat capacity of water = 4.2 J g-1 °C-1.
Answer» Calculate the amount of ice which is required to cool 150 g of water contained in a vessel of mass 100 g at 30°C, such that the final temperature of the mixture is 5^oC. Take specific heat capacity of material of vessel as 0.4 J g^-1 ^oC^-1 ; specific latent heat of fusion of ice = 336 J g^-1 ; specific heat capacity of water = 4.2 J g^-1 °C^-1.

Discussion

4.	Why can not we use superconductor to transport DC current ?
Answer» Why can not we use superconductor to transport DC current ?

Discussion

5.	How is the direction of electric current related to the direction of flow of electrons? Calculate the current in a circuit if 500C of charge passes through it in 10minutes.
Answer» How is the direction of electric current related to the direction of flow of electrons? Calculate the current in a circuit if 500C of charge passes through it in 10minutes.

Discussion

6.	There is an equiconvex lens glass lens with radius of curvature of each face as R and μ(glass) =1.5 and μ(water)=4/3 . If there is water on one side and air to the other side then equivalent focal length i
Answer» There is an equiconvex lens glass lens with radius of curvature of each face as R and μ(glass) =1.5 and μ(water)=4/3 . If there is water on one side and air to the other side then equivalent focal length i

Discussion

7.	While playing with prisms, Sushweta arranged three prisms as shown below (2nd prism inverted with respect to the other two) and made sunlight fall on the 1st prism.The colour(s) she would observe in regions A, B and C are respectively:
Answer» While playing with prisms, Sushweta arranged three prisms as shown below ( $2^{n d}$ prism inverted with respect to the other two) and made sunlight fall on the $1^{s t}$ prism. The colour(s) she would observe in regions A, B and C are respectively:

7.

While playing with prisms, Sushweta arranged three prisms as shown below (2nd prism inverted with respect to the other two) and made sunlight fall on the 1st prism.The colour(s) she would observe in regions A, B and C are respectively:

Answer»

While playing with prisms, Sushweta arranged three prisms as shown below ( $2^{n d}$ prism inverted with respect to the other two) and made sunlight fall on the $1^{s t}$ prism.

The colour(s) she would observe in regions A, B and C are respectively:

Discussion

8.	Energy released in the fission of a single 92U235 nucleus is 200 MeV. The fission rate of a 92U235 fuel reactor operating at a power level of 5 W is 1.56×105.5k s−1. The value of k is .(Integer only)
Answer» Energy released in the fission of a single $_{92} U^{235}$ nucleus is $200 MeV$ . The fission rate of a $_{92} U^{235}$ fuel reactor operating at a power level of $5 W$ is $1.56 \times 10^{5.5 k} s^{- 1}$ . The value of $k$ is .(Integer only)

Discussion

9.	Change in number of magnetic field lines induces:
Answer» Change in number of magnetic field lines induces:

Discussion

10.	The plates of charged condenser are connected by a conducting wire. The quantity of heat produced in the wire isa) Inversely proportional to the capacity of the condenserb) Inversely proportional to the square of the potential of the condenserc) Proportional to the length of wired) independent of the resistance of the wire
Answer» The plates of charged condenser are connected by a conducting wire. The quantity of heat produced in the wire is a) Inversely proportional to the capacity of the condenser b) Inversely proportional to the square of the potential of the condenser c) Proportional to the length of wire d) independent of the resistance of the wire

Discussion

11.	An uniform massless elastic spring has length a_1 when the tension in spring is T_1 and length a_2 when the tension in spring is T_2 What will be the length of spring when tension is T_3
Answer» An uniform massless elastic spring has length a_1 when the tension in spring is T_1 and length a_2 when the tension in spring is T_2 What will be the length of spring when tension is T_3

Discussion

12.	51.Find the potential at point P in the circuit attached below.
Answer» 51.Find the potential at point P in the circuit attached below.

Discussion

13.	A 4 ohm wire is doubled on it. Calculate the new resistance of the wire.
Answer» A 4 ohm wire is doubled on it. Calculate the new resistance of the wire.

Discussion

14.	Draw the graph for the following matrices.(i) (ii) (iii) (iv) (v) (vi)
Answer» Draw the graph for the following matrices. (i) (ii) (iii) (iv) (v) (vi)

14.

Draw the graph for the following matrices.(i) (ii) (iii) (iv) (v) (vi)

Answer»

Draw the graph for the following matrices.

(i)

(ii)

(iii)

(iv)

(v)

(vi)

Discussion

15.	Physical relation which consists of the physical quantity 'luminous intensity'.
Answer» Physical relation which consists of the physical quantity 'luminous intensity'.

Discussion

16.	If you are making maggie but its taking time because you have kept the temperature slightly lower than whats required ,so you want to speed up the process beacuse you are really hungry,you know that whole maggie,water and masala setup weighs 100 gms and specific heat is 0.9,you need 900 calories of heat more to make the maggie ,by how much amount you should increase the temperature?
Answer» If you are making maggie but its taking time because you have kept the temperature slightly lower than whats required ,so you want to speed up the process beacuse you are really hungry,you know that whole maggie,water and masala setup weighs 100 gms and specific heat is 0.9,you need 900 calories of heat more to make the maggie ,by how much amount you should increase the temperature?

Discussion

17.	A hemispherical bowl has a radius of 3.5 cm. What would be the volume of water it would contain?
Answer» A hemispherical bowl has a radius of 3.5 cm. What would be the volume of water it would contain?

Discussion

18.	Which one of the following fuels is considered as environment-friendly?
Answer» Which one of the following fuels is considered as environment-friendly?

Discussion

19.	If at the centre of the given solenoid, an iron ring is placed coaxially.Then identify in which direction will the magnetised iron ring's north-pole will be?
Answer» If at the centre of the given solenoid, an iron ring is placed coaxially.Then identify in which direction will the magnetised iron ring's north-pole will be?

19.

If at the centre of the given solenoid, an iron ring is placed coaxially.Then identify in which direction will the magnetised iron ring's north-pole will be?

Answer»

If at the centre of the given solenoid, an iron ring is placed coaxially.Then identify in which direction will the magnetised iron ring's north-pole will be?

Discussion

20.	A battery with EMF of 9 V is connected in series with an ammeter and a voltmeter. Resistance of these devices are unknown. If the voltmeter is connected to a resistance (its value is also unknown) in parallel, the ammeter reading will be doubled, and the voltmeter reading halved. What will be the voltmeter reading (in V) after connecting the resistance ?
Answer» A battery with EMF of $9 V$ is connected in series with an ammeter and a voltmeter. Resistance of these devices are unknown. If the voltmeter is connected to a resistance $($ its value is also unknown $)$ in parallel, the ammeter reading will be doubled, and the voltmeter reading halved. What will be the voltmeter reading (in $V$ ) after connecting the resistance ?

Discussion

21.	Now go back to A.1 and complete column (B). How much did you know already before you read the article?
Answer» Now go back to A.1 and complete column (B). How much did you know already before you read the article?

Discussion

22.	In a Searle's experiment, the diameter of the wire as measured by a screw gauge with least count 0.001 cm is 0.050 cm. The length, measured by a scale of least count 0.1 cm, is 110.0 cm. When a weight of 50 N is suspended from the wire, the extension is measured to be 0.125 cm by a micrometer of least count 0.001 cm. Find the maximum error in the measurement of Young's modulus of the material of the wire from these data. y=WA×LX Where W is the weight suspended from the wire, A is the cross section area, L is the length and X is the extension in the wire.
Answer» In a Searle's experiment, the diameter of the wire as measured by a screw gauge with least count 0.001 cm is 0.050 cm. The length, measured by a scale of least count 0.1 cm, is 110.0 cm. When a weight of 50 N is suspended from the wire, the extension is measured to be 0.125 cm by a micrometer of least count 0.001 cm. Find the maximum error in the measurement of Young's modulus of the material of the wire from these data. $y = \frac{W}{A} \times \frac{L}{X}$ Where W is the weight suspended from the wire, A is the cross section area, L is the length and X is the extension in the wire.

22.

In a Searle's experiment, the diameter of the wire as measured by a screw gauge with least count 0.001 cm is 0.050 cm. The length, measured by a scale of least count 0.1 cm, is 110.0 cm. When a weight of 50 N is suspended from the wire, the extension is measured to be 0.125 cm by a micrometer of least count 0.001 cm. Find the maximum error in the measurement of Young's modulus of the material of the wire from these data. y=WA×LX Where W is the weight suspended from the wire, A is the cross section area, L is the length and X is the extension in the wire.

Answer»

In a Searle's experiment, the diameter of the wire as measured by a screw gauge with least count 0.001 cm is 0.050 cm. The length, measured by a scale of least count 0.1 cm, is 110.0 cm. When a weight of 50 N is suspended from the wire, the extension is measured to be 0.125 cm by a micrometer of least count 0.001 cm. Find the maximum error in the measurement of Young's modulus of the material of the wire from these data.

$y = \frac{W}{A} \times \frac{L}{X}$
Where W is the weight suspended from the wire, A is the cross section area, L is the length and X is the extension in the wire.

Discussion

23.	Write a note on ISRO.
Answer» Write a note on ISRO.

Discussion

24.	An electron of charge e is moving round the nucleus of a hydrogen atom in a circular orbit of radius r. The Coulomb's force F between the two is:
Answer» An electron of charge $e$ is moving round the nucleus of a hydrogen atom in a circular orbit of radius $r$ . The Coulomb's force $F$ between the two is:

Discussion

25.	When n resistors of resistance R each is connected in series, the effective resistance is ___ and when they are connected in parallel, their effective resistance is ___.
Answer» When n resistors of resistance R each is connected in series, the effective resistance is ___ and when they are connected in parallel, their effective resistance is ___.

Discussion

26.	In an experiment to find the equivalent resistance of two resistors connected is series, a student used the circuit shown:This circuit will give :(1) correct reading for voltage V but incorrect reading for current I(2) correct reading for current I but incorrect reading for voltage V(3) correct reading for both voltage V and current I(4) Incorrect readings for both current I and voltage V
Answer» In an experiment to find the equivalent resistance of two resistors connected is series, a student used the circuit shown: This circuit will give : (1) correct reading for voltage V but incorrect reading for current I (2) correct reading for current I but incorrect reading for voltage V (3) correct reading for both voltage V and current I (4) Incorrect readings for both current I and voltage V

Discussion

27.	a body of mass m is projected from ground with speed u at an angle \varnothing with horizontal. the power delivered by gravity to it at half of maximum height from ground is
Answer» a body of mass m is projected from ground with speed u at an angle \varnothing with horizontal. the power delivered by gravity to it at half of maximum height from ground is

Discussion

28.	The focal length of a biconvex lens is f. If we cut the lens into two equal pieces as shown in the figure, the focal length of each piece will be ___.
Answer» The focal length of a biconvex lens is $f$ . If we cut the lens into two equal pieces as shown in the figure, the focal length of each piece will be ___.

Discussion

29.	The magnetic field of a solenoid can be made stronger by
Answer» The magnetic field of a solenoid can be made stronger by

Discussion

30.	When a piece of soft iron is placed inside a current-carrying coil, whose length is much greater than its diameter, the device formed is called
Answer» When a piece of soft iron is placed inside a current-carrying coil, whose length is much greater than its diameter, the device formed is called

Discussion

31.	Length of a vibrating string is halved. What will happen to its frequency?
Answer» Length of a vibrating string is halved. What will happen to its frequency?

Discussion

32.	Question 10A ladder 15 m long just reaches the top of a vertical wall. If the ladder makes an angle of 60∘ with the wall, then find the height of the wall.
Answer» Question 10 A ladder 15 m long just reaches the top of a vertical wall. If the ladder makes an angle of $60^{\circ}$ with the wall, then find the height of the wall.

Discussion

33.	Why change in magnetic field produces a current
Answer» Why change in magnetic field produces a current

Discussion

34.	Whatever be the position of the object, the image formed by a mirror is virtual, erect and smaller than the object. The mirror then must be : (a) plane (b) concave (c) convex (d) either concave or convex
Answer» Whatever be the position of the object, the image formed by a mirror is virtual, erect and smaller than the object. The mirror then must be : (a) plane (b) concave (c) convex (d) either concave or convex

Discussion

35.	two resistors are connected across an AC source of 5V. If the resistor R is replaced by a pure inductor of such magnitude that the value of current remains same, then the voltage across inductor is
Answer» two resistors are connected across an AC source of 5V. If the resistor R is replaced by a pure inductor of such magnitude that the value of current remains same, then the voltage across inductor is

Discussion

36.	Select the incorrect statement : (a) A machine always has the efficiency less than 100%. (b) The mechanical advantage of a machine can be less than 1. (c) A machine can be used as a speed multiplier. (d) A machine can have the mechanical advantage greater than the velocity ratio.
Answer» Select the incorrect statement : (a) A machine always has the efficiency less than $100 %$ . (b) The mechanical advantage of a machine can be less than 1. (c) A machine can be used as a speed multiplier. (d) A machine can have the mechanical advantage greater than the velocity ratio.

36.

Select the incorrect statement : (a) A machine always has the efficiency less than 100%. (b) The mechanical advantage of a machine can be less than 1. (c) A machine can be used as a speed multiplier. (d) A machine can have the mechanical advantage greater than the velocity ratio.

Answer»

Select the incorrect statement :

(a) A machine always has the efficiency less than $100 %$ .

(b) The mechanical advantage of a machine can be less than 1.

(c) A machine can be used as a speed multiplier.

(d) A machine can have the mechanical advantage greater than the velocity ratio.

Discussion

37.	In the shown figure a conducting ring of mass m=2 kg and radius R=0.5 m lies on a smooth horizontal plane with its plane vertical. The ring carries a current of I=1πA. A horizontal uniform magnetic field of B=12 T is switched on at t=0. The initial angular acceleration α in rad/sec2 of the ring will be 4x,then x is
Answer» In the shown figure a conducting ring of mass $m = 2 kg$ and radius $R = 0.5 m$ lies on a smooth horizontal plane with its plane vertical. The ring carries a current of $I = \frac{1}{π} A$ . A horizontal uniform magnetic field of $B = 12 T$ is switched on at $t = 0$ . The initial angular acceleration $α$ in ${rad/sec}^{2}$ of the ring will be $4 x$ ,then $x$ is

Discussion

38.	Two coaxial conducting circular coil of radius R are placed in a distance d(d
Answer» Two coaxial conducting circular coil of radius R are placed in a distance d(d<

Discussion

39.	A 10 m wide spacecraft moves through the interstellar space at a speed 3×107 ms −1. A magnetic field of B=3×10−10 T exists in the space in a direction perpendicular to the spacecraft motion. Treating the spacecraft as a conductor, find the emf induced across its width.
Answer» A $10 m$ wide spacecraft moves through the interstellar space at a speed $3 \times 10^{7} {ms}^{- 1} .$ A magnetic field of $B = 3 \times 10^{- 10} T$ exists in the space in a direction perpendicular to the spacecraft motion. Treating the spacecraft as a conductor, find the emf induced across its width.

Discussion

40.	4.Number of Faraday required to deposit 1 g- eq ol aluminum from AlCl3
Answer» 4.Number of Faraday required to deposit 1 g- eq ol aluminum from AlCl3

Discussion

41.	One of the reasons for myopia is
Answer» One of the reasons for myopia is

Discussion

42.	Find the principle behind all the given pictures and try solving the puzzle for the force behind it.
Answer» Find the principle behind all the given pictures and try solving the puzzle for the force behind it.

Discussion

43.	A body of mass m is kept at a small height h above the ground. If the radius of the earth is R and its mass is M, the potential energy of the body and earth system (with h = ∞ being the reference position) is
Answer» A body of mass m is kept at a small height h above the ground. If the radius of the earth is R and its mass is M, the potential energy of the body and earth system (with h = $\infty$ being the reference position) is

Discussion

44.	An object is released at one bank into a river flowing with speed 5 km/h towards east. Air is blowing with speed 5 km/h towards north. If width of river is 200 m, then time taken by floating object to reach the other bank is (Assume the object moves under effect of river and wind both)
Answer» An object is released at one bank into a river flowing with speed 5 km/h towards east. Air is blowing with speed 5 km/h towards north. If width of river is 200 m, then time taken by floating object to reach the other bank is (Assume the object moves under effect of river and wind both)

Discussion

45.	The following circuit diagram shows the experimental set up for the study of dependence of current on potential difference. Which two circuit components are connected in series?
Answer» The following circuit diagram shows the experimental set up for the study of dependence of current on potential difference. Which two circuit components are connected in series?

45.

The following circuit diagram shows the experimental set up for the study of dependence of current on potential difference. Which two circuit components are connected in series?

Answer»

The following circuit diagram shows the experimental set up for the study of dependence of current on potential difference. Which two circuit components are connected in series?

Discussion

46.	A coil of inductance 8.4 mH and a resistance 6 ohm is connected to a 12 V battery in series. The current in the coil is 1 A at approximately the time :-(1) 500 s (2) 20 s (3) 35 ms (4) 1 ms
Answer» A coil of inductance 8.4 mH and a resistance 6 ohm is connected to a 12 V battery in series. The current in the coil is 1 A at approximately the time :- (1) 500 s (2) 20 s (3) 35 ms (4) 1 ms

Discussion

47.	Infrastructural details of country Normans Land. - Maximum possible electricity production in aear (in kwh) = Generating capacity in kw × number if hours in a year - Capacity utilization % =Actual electricity productionMaximum possible electricity production× 100 If efficiency of power production is defined as . 85 × capacity utilization, then what was the efficiency in 1985(approximately).
Answer» Infrastructural details of country Normans Land. - Maximum possible electricity production in aear (in kwh) = Generating capacity in kw $\times$ number if hours in a year - Capacity utilization % $= \frac{A c t u a l e l e c t r i c i t y p r o d u c t i o n}{M a x i m u m p o s s i b l e e l e c t r i c i t y p r o d u c t i o n} \times$ 100 If efficiency of power production is defined as . 85 $\times$ capacity utilization, then what was the efficiency in 1985(approximately).

Discussion

48.	What is the relationship between the focal length f and radius of curvature R for a spherical mirror?
Answer» What is the relationship between the focal length $f$ and radius of curvature $R$ for a spherical mirror?

Discussion

49.	What is the what is the relationship between electromagnetism and Optics
Answer» What is the what is the relationship between electromagnetism and Optics

Discussion

50.	If resistance of 60cm nichrome wire is 2.5ohms. What should be length of wire is required to have resistance of 4.5 ohms?
Answer» If resistance of 60cm nichrome wire is 2.5ohms. What should be length of wire is required to have resistance of 4.5 ohms?

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

The flow of which of the following fundamental particles leads to the existence of electricity?

Why can not we use superconductor to transport DC current ?

How is the direction of electric current related to the direction of flow of electrons? Calculate the current in a circuit if 500C of charge passes through it in 10minutes.

There is an equiconvex lens glass lens with radius of curvature of each face as R and μ(glass) =1.5 and μ(water)=4/3 . If there is water on one side and air to the other side then equivalent focal length i

While playing with prisms, Sushweta arranged three prisms as shown below (2nd prism inverted with respect to the other two) and made sunlight fall on the 1st prism.The colour(s) she would observe in regions A, B and C are respectively:

Energy released in the fission of a single 92U235 nucleus is 200 MeV. The fission rate of a 92U235 fuel reactor operating at a power level of 5 W is 1.56×105.5k s−1. The value of k is .(Integer only)

Change in number of magnetic field lines induces:

An uniform massless elastic spring has length a_1 when the tension in spring is T_1 and length a_2 when the tension in spring is T_2 What will be the length of spring when tension is T_3

51.Find the potential at point P in the circuit attached below.

A 4 ohm wire is doubled on it. Calculate the new resistance of the wire.

Draw the graph for the following matrices.(i) (ii) (iii) (iv) (v) (vi)

Physical relation which consists of the physical quantity 'luminous intensity'.

A hemispherical bowl has a radius of 3.5 cm. What would be the volume of water it would contain?

Which one of the following fuels is considered as environment-friendly?

If at the centre of the given solenoid, an iron ring is placed coaxially.Then identify in which direction will the magnetised iron ring's north-pole will be?

Now go back to A.1 and complete column (B). How much did you know already before you read the article?

Write a note on ISRO.

An electron of charge e is moving round the nucleus of a hydrogen atom in a circular orbit of radius r. The Coulomb's force F between the two is:

When n resistors of resistance R each is connected in series, the effective resistance is ___ and when they are connected in parallel, their effective resistance is ___.

a body of mass m is projected from ground with speed u at an angle \varnothing with horizontal. the power delivered by gravity to it at half of maximum height from ground is

The focal length of a biconvex lens is f. If we cut the lens into two equal pieces as shown in the figure, the focal length of each piece will be ___.

The magnetic field of a solenoid can be made stronger by

When a piece of soft iron is placed inside a current-carrying coil, whose length is much greater than its diameter, the device formed is called

Length of a vibrating string is halved. What will happen to its frequency?

Question 10A ladder 15 m long just reaches the top of a vertical wall. If the ladder makes an angle of 60∘ with the wall, then find the height of the wall.

Why change in magnetic field produces a current

Whatever be the position of the object, the image formed by a mirror is virtual, erect and smaller than the object. The mirror then must be : (a) plane (b) concave (c) convex (d) either concave or convex

two resistors are connected across an AC source of 5V. If the resistor R is replaced by a pure inductor of such magnitude that the value of current remains same, then the voltage across inductor is

Select the incorrect statement : (a) A machine always has the efficiency less than 100%. (b) The mechanical advantage of a machine can be less than 1. (c) A machine can be used as a speed multiplier. (d) A machine can have the mechanical advantage greater than the velocity ratio.

Two coaxial conducting circular coil of radius R are placed in a distance d(d

A 10 m wide spacecraft moves through the interstellar space at a speed 3×107 ms −1. A magnetic field of B=3×10−10 T exists in the space in a direction perpendicular to the spacecraft motion. Treating the spacecraft as a conductor, find the emf induced across its width.

4.Number of Faraday required to deposit 1 g- eq ol aluminum from AlCl3

One of the reasons for myopia is

Find the principle behind all the given pictures and try solving the puzzle for the force behind it.

A body of mass m is kept at a small height h above the ground. If the radius of the earth is R and its mass is M, the potential energy of the body and earth system (with h = ∞ being the reference position) is

An object is released at one bank into a river flowing with speed 5 km/h towards east. Air is blowing with speed 5 km/h towards north. If width of river is 200 m, then time taken by floating object to reach the other bank is (Assume the object moves under effect of river and wind both)

The following circuit diagram shows the experimental set up for the study of dependence of current on potential difference. Which two circuit components are connected in series?

A coil of inductance 8.4 mH and a resistance 6 ohm is connected to a 12 V battery in series. The current in the coil is 1 A at approximately the time :-(1) 500 s (2) 20 s (3) 35 ms (4) 1 ms

What is the relationship between the focal length f and radius of curvature R for a spherical mirror?

What is the what is the relationship between electromagnetism and Optics

If resistance of 60cm nichrome wire is 2.5ohms. What should be length of wire is required to have resistance of 4.5 ohms?

When n resistors of resistance R each is connected in series, the effective resistance is _ and when they are connected in parallel, their effective resistance is _.