16569 + Interview Questions in Physics Page 22 InterviewSolution

1051.	A wire of resistance 10Ω is cut such that its area becomes 13rd. If the length is unchanged then what will be the new resistance?
Answer» A wire of resistance $10 Ω$ is cut such that its area becomes $\frac{1}{3}$ rd. If the length is unchanged then what will be the new resistance?

Discussion

1052.	List four characteristics of the images formed by plane mirrors.
Answer» List four characteristics of the images formed by plane mirrors.

Discussion

1053.	The process of changing signal from graph 1 to graph 2 is
Answer» The process of changing signal from graph 1 to graph 2 is

Discussion

1054.	The slope at point 'C' and deflection at point B in the beam as shown in figure are respectively
Answer» The slope at point 'C' and deflection at point B in the beam as shown in figure are respectively

Discussion

1055.	. The natural lengths of massless spring is x(spring constant k), it is slowly stretched byapplying an external force. The work done tostretch the spring from length 3x to 4x is(1) 1.5kx(2) 2.5kx2(3) 4kx2(4) kx2
Answer» . The natural lengths of massless spring is x(spring constant k), it is slowly stretched byapplying an external force. The work done tostretch the spring from length 3x to 4x is(1) 1.5kx(2) 2.5kx2(3) 4kx2(4) kx2

Discussion

1056.	Question 2 Choose the incorrect statement. (a) A switch is the source of electric current in a circuit. (b) A switch help to complete or break the circuit. (c) A switch helps us to use electricity as per our requirement. (d) When the switch is open there is an air gap between its terminals.
Answer» Question 2 Choose the incorrect statement. (a) A switch is the source of electric current in a circuit. (b) A switch help to complete or break the circuit. (c) A switch helps us to use electricity as per our requirement. (d) When the switch is open there is an air gap between its terminals.

1056.

Question 2 Choose the incorrect statement. (a) A switch is the source of electric current in a circuit. (b) A switch help to complete or break the circuit. (c) A switch helps us to use electricity as per our requirement. (d) When the switch is open there is an air gap between its terminals.

Answer»

Question 2

Choose the incorrect statement.

(a) A switch is the source of electric current in a circuit.

(b) A switch help to complete or break the circuit.

(c) A switch helps us to use electricity as per our requirement.

(d) When the switch is open there is an air gap between its terminals.

Discussion

1057.	nttwo circular coil 1 and 2 are made from same wire bt radius of ist coil is twice of 2 nd coil . what is the ratio of potential differrence applied across them ,so that the magnetic field at the centre is the samen
Answer» nttwo circular coil 1 and 2 are made from same wire bt radius of ist coil is twice of 2 nd coil . what is the ratio of potential differrence applied across them ,so that the magnetic field at the centre is the samen

Discussion

1058.	A copper rod of length / is rotating about mid-point of rod, perpendicular to the magnetic field B with constantangular velocity o. The induced emf between the two ends is16.21B012(1)(3) 2Bol2(2) Bol2(4) Zero
Answer» A copper rod of length / is rotating about mid-point of rod, perpendicular to the magnetic field B with constantangular velocity o. The induced emf between the two ends is16.21B012(1)(3) 2Bol2(2) Bol2(4) Zero

Discussion

1059.	Two sounds having the same speed in a medium are having wavelengths 1.3 m and 3.9 m. A person listens to these sounds. What difference would the listener feel?
Answer» Two sounds having the same speed in a medium are having wavelengths $1.3 m$ and $3.9 m$ . A person listens to these sounds. What difference would the listener feel?

Discussion

1060.	Calculate the value of the resistance which must be connected to a 15 Ω resistance to provide an effective resistance of 6 Ω
Answer» Calculate the value of the resistance which must be connected to a 15 Ω resistance to provide an effective resistance of 6 Ω

Discussion

1061.	The magnetic field associated with a current-carrying straight conductor is in anticlockwise direction. If the conductor was held along the east-west direction, what will be the direction of current through it ? Name and state the rule applied to determine the direction of current ?
Answer» The magnetic field associated with a current-carrying straight conductor is in anticlockwise direction. If the conductor was held along the east-west direction, what will be the direction of current through it ? Name and state the rule applied to determine the direction of current ?

Discussion

1062.	An ultrasonic wave is sent from a ship towards the bottom of the sea. It is found that the time interval between the sending and the receiving of the wave is 1.5 second. The depth of the sea [if the velocity of sound in sea water is 1400 m s-1] is:
Answer» An ultrasonic wave is sent from a ship towards the bottom of the sea. It is found that the time interval between the sending and the receiving of the wave is 1.5 second. The depth of the sea [if the velocity of sound in sea water is 1400 m s^-1] is:

1062.

An ultrasonic wave is sent from a ship towards the bottom of the sea. It is found that the time interval between the sending and the receiving of the wave is 1.5 second. The depth of the sea [if the velocity of sound in sea water is 1400 m s-1] is:

Answer»

An ultrasonic wave is sent from a ship towards the bottom of the sea. It is found that the time interval between the sending and the receiving of the wave is 1.5 second.

The depth of the sea [if the velocity of sound in sea water is 1400 m s^-1] is:

Discussion

1063.	Where will parallel rays meet/appears to meet ?
Answer» Where will parallel rays meet/appears to meet ?

1063.

Where will parallel rays meet/appears to meet ?

Answer»

Where will parallel rays meet/appears to meet ?

Discussion

1064.	Two resistors of resistor 2Ω and 5Ω are connected in series with a 7v battery. Find the potential difference across the 5Ω resistor.
Answer» Two resistors of resistor 2Ω and 5Ω are connected in series with a 7v battery. Find the potential difference across the 5Ω resistor.

1064.

Two resistors of resistor 2Ω and 5Ω are connected in series with a 7v battery. Find the potential difference across the 5Ω resistor.

Answer»

Two resistors of resistor 2Ω and 5Ω are connected in series with a 7v battery. Find the potential difference across the 5Ω resistor.

Discussion

1065.	Question 5 (a) What is (a) the highest total resistance that can be secured by combinations of four coils of resistance 4Ω,8Ω,12Ω and 24Ω?
Answer» Question 5 (a) What is (a) the highest total resistance that can be secured by combinations of four coils of resistance $4 Ω, 8 Ω, 12 Ω$ and $24 Ω$ ?

Discussion

1066.	what is the reaction force of weight
Answer» what is the reaction force of weight

Discussion

1067.	In the circuit given below, if the equivalent resistance between points a and b is R, then find the value of R in terms of r.
Answer» In the circuit given below, if the equivalent resistance between points $a$ and $b$ is $R$ , then find the value of $R$ in terms of $r$ .

Discussion

1068.	The frequency of power supply used in India is ___ Hz.
Answer» The frequency of power supply used in India is ___ Hz.

Discussion

1069.	What is the difference between optical density and mass density
Answer» What is the difference between optical density and mass density

Discussion

1070.	Does magnetic field have mass ??
Answer» Does magnetic field have mass ??

Discussion

1071.	The near point and far point of a person are 40 cm and 250 cm respectively. Find the power of the lens he/she should use while reading at 25 cm.
Answer» The near point and far point of a person are $40 cm$ and $250 cm$ respectively. Find the power of the lens he/she should use while reading at $25 cm$ .

Discussion

1072.	What should be the maximumacceptance at the air core interface of an opticalfibre, if n, and n2 are the refractive indices of thecore and the cladding respectively?22.angle of1 12(1) sin n(2) sin-1-n를(3) tan-112(4) sin-1
Answer» What should be the maximumacceptance at the air core interface of an opticalfibre, if n, and n2 are the refractive indices of thecore and the cladding respectively?22.angle of1 12(1) sin n(2) sin-1-n를(3) tan-112(4) sin-1

Discussion

1073.	Q.3 a coin is placed at the bottom of a tank which is filled by two liquid layers as shown . the apparent depth of coin from top surface of normal viewing is
Answer» Q.3 a coin is placed at the bottom of a tank which is filled by two liquid layers as shown . the apparent depth of coin from top surface of normal viewing is

Discussion

1074.	Three charges +3Q,+2Q and −Q respectively are located at a distance "a" from the origin as shown in the figure. (k=14πϵ0). A fourth charge +3Q is slowly moved in from inifinite to the point O. The work done by an external agent in this process is
Answer» Three charges $+ 3 Q, + 2 Q$ and $- Q$ respectively are located at a distance $" a "$ from the origin as shown in the figure. $(k = \frac{1}{4 π ϵ_{0}})$ . A fourth charge $+ 3 Q$ is slowly moved in from inifinite to the point O. The work done by an external agent in this process is

Discussion

1075.	In a full wave rectifier circuit operating from 50Hmains frequency, the fundamental frequency in theripple would be(1) 25 Hz(3) 70.7 Hz(2) 50 Hz(4) 100 Hzdiodo the reverse bias
Answer» In a full wave rectifier circuit operating from 50Hmains frequency, the fundamental frequency in theripple would be(1) 25 Hz(3) 70.7 Hz(2) 50 Hz(4) 100 Hzdiodo the reverse bias

Discussion

1076.	What is W in sound power is it watt or else what is this unit.
Answer» What is W in sound power is it watt or else what is this unit.

Discussion

1077.	State condition in each case for the magnitude of force on a current carrying conductor placed in a magnetic field to be (a) zero, and (b) maximum.
Answer» State condition in each case for the magnitude of force on a current carrying conductor placed in a magnetic field to be (a) zero, and (b) maximum.

Discussion

1078.	Question 157 Ajay had a 1 cm piece of gum. He put it through repeater machine given below and it came out 1100000 cm long. What is the missing value ?
Answer» Question 157 Ajay had a 1 cm piece of gum. He put it through repeater machine given below and it came out $\frac{1}{100000} c m$ long. What is the missing value ?

1078.

Question 157 Ajay had a 1 cm piece of gum. He put it through repeater machine given below and it came out 1100000 cm long. What is the missing value ?

Answer»

Question 157

Ajay had a 1 cm piece of gum. He put it through repeater machine given below and it came out $\frac{1}{100000} c m$ long. What is the missing value ?

Discussion

1079.	Explain the working of a hydroelectric power plant with schematic diagram. [5 MARKS]
Answer» Explain the working of a hydroelectric power plant with schematic diagram. [5 MARKS]

Discussion

1080.	A given length L of wire carries a current I. The wire can be formed into a circular coil of any number of turns. The maximum value of the torque τ that can be developed on the coil when placed in a given magnetic field B is τ=IBL2xπ. The value of x is ______.
Answer» A given length $L$ of wire carries a current $I$ . The wire can be formed into a circular coil of any number of turns. The maximum value of the torque $τ$ that can be developed on the coil when placed in a given magnetic field $B$ is $τ = \frac{I B L^{2}}{x π}$ . The value of $x$ is ______.

Discussion

1081.	62. A mass M is broken intom two parts of masses m1 an m2 . How are m1 and m2 related so that foce of gravitational attraction between the two parts is maximum.?
Answer» 62. A mass M is broken intom two parts of masses m1 an m2 . How are m1 and m2 related so that foce of gravitational attraction between the two parts is maximum.?

Discussion

1082.	The potential energy U of a diatomic molecule is a function dependent on r (interatomic distance) as U=αr10−βr5−3. Where, a and b are positive constants. The equilibrium distance between two atoms will be (2αβ)ab, then a=________
Answer» The potential energy $U$ of a diatomic molecule is a function dependent on $r$ $($ interatomic distance $)$ as $U = \frac{α}{r^{10}} - \frac{β}{r^{5}} - 3$ . Where, $a$ and $b$ are positive constants. The equilibrium distance between two atoms will be ${(\frac{2 α}{β})}^{\frac{a}{b}}$ , then $a =$ ________

Discussion

1083.	27. how to find domenson of bar
Answer» 27. how to find domenson of bar

Discussion

1084.	Find the net resistance between points A and B :
Answer» Find the net resistance between points $A$ and $B$ :

Discussion

1085.	Is the body in rotational equilibrium? But the net torque about p and q is not zero right how? Plz explain thanks.
Answer» Is the body in rotational equilibrium? But the net torque about p and q is not zero right how? Plz explain thanks.

Discussion

1086.	If a spherical lens has a power of, - 0.25 D, the focal length of this lens will be : (a) - 4 cm (b) - 400 mm (c) - 4 m (d) - 40 m
Answer» If a spherical lens has a power of, - 0.25 D, the focal length of this lens will be : (a) - 4 cm (b) - 400 mm (c) - 4 m (d) - 40 m

Discussion

1087.	in the equation, Change in U = q + W, when the work done is more, the heat change is less. why is it so?
Answer» in the equation, Change in U = q + W, when the work done is more, the heat change is less. why is it so?

Discussion

1088.	Which one of the following is not a source of non-conventional energy?
Answer» Which one of the following is not a source of non-conventional energy?

Discussion

1089.	The unit of current is ________
Answer» The unit of current is ________

Discussion

1090.	What is the power output of U 235,92 reactor if it takes 30 days to use up 2 kg of fuel and if each fission gives 185 MeV of usable energy?
Answer» What is the power output of U 235,92 reactor if it takes 30 days to use up 2 kg of fuel and if each fission gives 185 MeV of usable energy?

Discussion

1091.	Name one defect of vision that cannot be corrected by any type of spectacle lens.
Answer» Name one defect of vision that cannot be corrected by any type of spectacle lens.

Discussion

1092.	A resistance coil of 60 Ω is immersed in 42000 gm of water. A current of 7 A is passed through it. The rise in temperature of water per minute is (Specific heat of water =4200 Jkg−1K−1)
Answer» A resistance coil of $60 Ω$ is immersed in $42000 gm$ of water. A current of $7 A$ is passed through it. The rise in temperature of water per minute is (Specific heat of water $= 4200 {Jkg}^{- 1} K^{- 1}$ )

Discussion

1093.	If fv and fR are the focal lengths of a convex lens for violet and red light respectively and Fv and FR are the focal lengths of concave lens for violet and red light respectively, then we have (a) fv < fR and Fv > FR (b) fv < fR and Fv < FR (c) fv > fR and Fv > FR (d) fv > fR and Fv < FR (here if we consider the fact that focal length of a concave lens is negative,we get option (a)0 but it is given anwer is (b) how ?
Answer» If fv and fR are the focal lengths of a convex lens for violet and red light respectively and Fv and FR are the focal lengths of concave lens for violet and red light respectively, then we have (a) fv < fR and Fv > FR (b) fv < fR and Fv < FR (c) fv > fR and Fv > FR (d) fv > fR and Fv < FR (here if we consider the fact that focal length of a concave lens is negative,we get option (a)0 but it is given anwer is (b) how ?

Discussion

1094.	Which of the quantities get transferred during the propagation of a wave:
Answer» Which of the quantities get transferred during the propagation of a wave:

Discussion

1095.	98. For the given lens,the magnification was found to be twice as large when the object was 0.15m distance from it as when the distance was 0.2m. Find the power of the lens.
Answer» 98. For the given lens,the magnification was found to be twice as large when the object was 0.15m distance from it as when the distance was 0.2m. Find the power of the lens.

Discussion

1096.	When the material A mined from the earth is heated strongly in an insufficeint supply of air, it produces a solid fuel B which consists mainly of carbon. When another material C obtained from trees is heated in an insufficient supply of air, it produces another solid fuel D which also consists mainly of carbon. Name A, B, C and D.
Answer» When the material A mined from the earth is heated strongly in an insufficeint supply of air, it produces a solid fuel B which consists mainly of carbon. When another material C obtained from trees is heated in an insufficient supply of air, it produces another solid fuel D which also consists mainly of carbon. Name A, B, C and D.

Discussion

1097.	The diagram below shows a rod lifting a stone. (a) Mark position of fulcrum F and draw arrows to show the directions of load L and effort E . (b) What class of lever is the rod ? (c) Give one more example of the same class of lever stated in part (b).
Answer» The diagram below shows a rod lifting a stone. (a) Mark position of fulcrum F and draw arrows to show the directions of load L and effort E . (b) What class of lever is the rod ? (c) Give one more example of the same class of lever stated in part (b).

1097.

The diagram below shows a rod lifting a stone. (a) Mark position of fulcrum F and draw arrows to show the directions of load L and effort E . (b) What class of lever is the rod ? (c) Give one more example of the same class of lever stated in part (b).

Answer»

The diagram below shows a rod lifting a stone.

(a) Mark position of fulcrum F and draw arrows to show the directions of load L and effort E . (b) What class of lever is the rod ? (c) Give one more example of the same class of lever stated in part (b).

Discussion

1098.	How unit of electric field intensity in Newton per coulumb?
Answer» How unit of electric field intensity in Newton per coulumb?

Discussion

1099.	68.A particle is moving with constant speed v in xy plane as shown in figure. The magnitude of its angular velocity about point O is
Answer» 68.A particle is moving with constant speed v in xy plane as shown in figure. The magnitude of its angular velocity about point O is

Discussion

1100.	Consider a fusion reaction 4He+4He→8Be. The Q− value of the reaction is −(90+n) k eV. The value of n is (integer only).Take 1 amu=930c2 M eVAtomic mass of 8Be=8.0053 u ; 4He=4.0026 u
Answer» Consider a fusion reaction $^{4} He +^{4} He \to^{8} Be .$ The $Q -$ value of the reaction is $- (90 + n) k eV .$ The value of $n$ is (integer only). Take $1 amu = \frac{930}{c^{2}} M eV {Atomic mass of}^{8} Be = 8.0053 u;^{4} He = 4.0026 u$

Discussion

Explore topic-wise InterviewSolutions in .

A wire of resistance 10Ω is cut such that its area becomes 13rd. If the length is unchanged then what will be the new resistance?

List four characteristics of the images formed by plane mirrors.

The process of changing signal from graph 1 to graph 2 is

The slope at point 'C' and deflection at point B in the beam as shown in figure are respectively

. The natural lengths of massless spring is x(spring constant k), it is slowly stretched byapplying an external force. The work done tostretch the spring from length 3x to 4x is(1) 1.5kx(2) 2.5kx2(3) 4kx2(4) kx2

Question 2 Choose the incorrect statement. (a) A switch is the source of electric current in a circuit. (b) A switch help to complete or break the circuit. (c) A switch helps us to use electricity as per our requirement. (d) When the switch is open there is an air gap between its terminals.

nttwo circular coil 1 and 2 are made from same wire bt radius of ist coil is twice of 2 nd coil . what is the ratio of potential differrence applied across them ,so that the magnetic field at the centre is the samen

A copper rod of length / is rotating about mid-point of rod, perpendicular to the magnetic field B with constantangular velocity o. The induced emf between the two ends is16.21B012(1)(3) 2Bol2(2) Bol2(4) Zero

Two sounds having the same speed in a medium are having wavelengths 1.3 m and 3.9 m. A person listens to these sounds. What difference would the listener feel?

Calculate the value of the resistance which must be connected to a 15 Ω resistance to provide an effective resistance of 6 Ω

The magnetic field associated with a current-carrying straight conductor is in anticlockwise direction. If the conductor was held along the east-west direction, what will be the direction of current through it ? Name and state the rule applied to determine the direction of current ?

An ultrasonic wave is sent from a ship towards the bottom of the sea. It is found that the time interval between the sending and the receiving of the wave is 1.5 second. The depth of the sea [if the velocity of sound in sea water is 1400 m s-1] is:

Where will parallel rays meet/appears to meet ?

Two resistors of resistor 2Ω and 5Ω are connected in series with a 7v battery. Find the potential difference across the 5Ω resistor.

Question 5 (a) What is (a) the highest total resistance that can be secured by combinations of four coils of resistance 4Ω,8Ω,12Ω and 24Ω?

what is the reaction force of weight

In the circuit given below, if the equivalent resistance between points a and b is R, then find the value of R in terms of r.

The frequency of power supply used in India is ___ Hz.

What is the difference between optical density and mass density

Does magnetic field have mass ??

The near point and far point of a person are 40 cm and 250 cm respectively. Find the power of the lens he/she should use while reading at 25 cm.

What should be the maximumacceptance at the air core interface of an opticalfibre, if n, and n2 are the refractive indices of thecore and the cladding respectively?22.angle of1 12(1) sin n(2) sin-1-n를(3) tan-112(4) sin-1

Q.3 a coin is placed at the bottom of a tank which is filled by two liquid layers as shown . the apparent depth of coin from top surface of normal viewing is

Three charges +3Q,+2Q and −Q respectively are located at a distance "a" from the origin as shown in the figure. (k=14πϵ0). A fourth charge +3Q is slowly moved in from inifinite to the point O. The work done by an external agent in this process is

In a full wave rectifier circuit operating from 50Hmains frequency, the fundamental frequency in theripple would be(1) 25 Hz(3) 70.7 Hz(2) 50 Hz(4) 100 Hzdiodo the reverse bias

What is W in sound power is it watt or else what is this unit.

State condition in each case for the magnitude of force on a current carrying conductor placed in a magnetic field to be (a) zero, and (b) maximum.

Question 157 Ajay had a 1 cm piece of gum. He put it through repeater machine given below and it came out 1100000 cm long. What is the missing value ?

Explain the working of a hydroelectric power plant with schematic diagram. [5 MARKS]

A given length L of wire carries a current I. The wire can be formed into a circular coil of any number of turns. The maximum value of the torque τ that can be developed on the coil when placed in a given magnetic field B is τ=IBL2xπ. The value of x is ______.

62. A mass M is broken intom two parts of masses m1 an m2 . How are m1 and m2 related so that foce of gravitational attraction between the two parts is maximum.?

The potential energy U of a diatomic molecule is a function dependent on r (interatomic distance) as U=αr10−βr5−3. Where, a and b are positive constants. The equilibrium distance between two atoms will be (2αβ)ab, then a=________

27. how to find domenson of bar

Find the net resistance between points A and B :

Is the body in rotational equilibrium? But the net torque about p and q is not zero right how? Plz explain thanks.

If a spherical lens has a power of, - 0.25 D, the focal length of this lens will be : (a) - 4 cm (b) - 400 mm (c) - 4 m (d) - 40 m

in the equation, Change in U = q + W, when the work done is more, the heat change is less. why is it so?

Which one of the following is not a source of non-conventional energy?

The unit of current is ________

What is the power output of U 235,92 reactor if it takes 30 days to use up 2 kg of fuel and if each fission gives 185 MeV of usable energy?

Name one defect of vision that cannot be corrected by any type of spectacle lens.

A resistance coil of 60 Ω is immersed in 42000 gm of water. A current of 7 A is passed through it. The rise in temperature of water per minute is (Specific heat of water =4200 Jkg−1K−1)

Which of the quantities get transferred during the propagation of a wave:

98. For the given lens,the magnification was found to be twice as large when the object was 0.15m distance from it as when the distance was 0.2m. Find the power of the lens.

The diagram below shows a rod lifting a stone. (a) Mark position of fulcrum F and draw arrows to show the directions of load L and effort E . (b) What class of lever is the rod ? (c) Give one more example of the same class of lever stated in part (b).

How unit of electric field intensity in Newton per coulumb?

68.A particle is moving with constant speed v in xy plane as shown in figure. The magnitude of its angular velocity about point O is

Consider a fusion reaction 4He+4He→8Be. The Q− value of the reaction is −(90+n) k eV. The value of n is (integer only).Take 1 amu=930c2 M eVAtomic mass of 8Be=8.0053 u ; 4He=4.0026 u