50278 + Interview Questions in Physics

1.	At room temperature (27.0 °C) the resistance of a heating elementis 100 W. What is the temperature of the element if the resistance isfound to be 117 W, given that the temperature coefficient of thematerial of the resistor is 1.70 × 10–4 °C–1.
Answer» At room temperature (27.0 °C) the resistance of a heating elementis 100 W. What is the temperature of the element if the resistance isfound to be 117 W, given that the temperature coefficient of thematerial of the resistor is 1.70 × 10–4 °C–1.

Discussion

2.	In a full wave rectifier circuit operating from 50 Hz mains frequency, the fundamental frequency in the ripple would be
Answer» In a full wave rectifier circuit operating from $50 Hz$ mains frequency, the fundamental frequency in the ripple would be

Discussion

3.	A 2 V battery is connected across the points A and B as shown in the figure given below. Assuming that the resistance of each diode is zero in forward bias and infinity in reverse bias, the current supplied by the battery when its positive terminal is connected to A is
Answer» A $2 V$ battery is connected across the points A and B as shown in the figure given below. Assuming that the resistance of each diode is zero in forward bias and infinity in reverse bias, the current supplied by the battery when its positive terminal is connected to A is

Discussion

4.	A test tube of cross-sectional area a has some lead shots in it. The total mass is m. It floats upright in liquid of density d. when pushed down little and released, it oscillates up and down with a period T. Use dimensional considerations and choose the correct relationship from the following.
Answer» A test tube of cross-sectional area a has some lead shots in it. The total mass is m. It floats upright in liquid of density d. when pushed down little and released, it oscillates up and down with a period T. Use dimensional considerations and choose the correct relationship from the following.

Discussion

5.	A 13m ladder is placed against a smooth vertical wall with its lower end 5m from the wall. what should be the minimum coefficient of friction between ladder and floor so that it remains in equilibrium.
Answer» A 13m ladder is placed against a smooth vertical wall with its lower end 5m from the wall. what should be the minimum coefficient of friction between ladder and floor so that it remains in equilibrium.

Discussion

6.	Two identically charged spheres are suspended by strings of equal length. The strings make an angle of 30 degrees with each other. When suspended in a liquid of density 0.8gm/cc, the angle remains same. What's the dielectric constant of liquid? Density of sphere = 1.6gm/cc.
Answer» Two identically charged spheres are suspended by strings of equal length. The strings make an angle of 30 degrees with each other. When suspended in a liquid of density 0.8gm/cc, the angle remains same. What's the dielectric constant of liquid? Density of sphere = 1.6gm/cc.

Discussion

7.	Consider the common emitter circuit shown in the figure below:If the value of β=99, then the value of the lower 3-dB frequency is ________Hz.(Assume VT=25 mV)7.95
Answer» Consider the common emitter circuit shown in the figure below: $If the value of β = 99, then the value of the lower 3-dB frequency is ________Hz.$ $(Assume V_{T} = 25 mV)$ 7.95

Discussion

8.	A weightless rod of length 2l carries two equal masses ′m′, one tied at lower end A and the other at the middle of the rod at B. The rod can rotate in a vertical plane about a fixed horizontal axis passing through C. The rod is released from rest from the horizontal position. The speed of the mass B at the instant the rod becomes vertical is:
Answer» A weightless rod of length $2 l$ carries two equal masses $^{'} m^{'}$ , one tied at lower end $A$ and the other at the middle of the rod at $B$ . The rod can rotate in a vertical plane about a fixed horizontal axis passing through $C$ . The rod is released from rest from the horizontal position. The speed of the mass $B$ at the instant the rod becomes vertical is:

Discussion

9.	One plate of a capacitor is connected to a spring as shown. Area of both the plates is A and separation is d when capacitor is uncharged. When capacitor is charged in steady state separation between the plate is 0.8d the force constant of the spring is
Answer» One plate of a capacitor is connected to a spring as shown. Area of both the plates is $A$ and separation is $d$ when capacitor is uncharged. When capacitor is charged in steady state separation between the plate is $0.8 d$ the force constant of the spring is

Discussion

10.	A glass flask is filled upto a mark with 50 cm3 of mercury at 18∘C. If the flask and contents are heated to 38∘C, how much mercury will be above the mark?α for glass is 10×10−6∘C−1 and coefficient of volumetric expansion of mercury is 180×10−6∘C−1
Answer» A glass flask is filled upto a mark with $50 {cm}^{3}$ of mercury at $18^{\circ} C$ . If the flask and contents are heated to $38^{\circ} C$ , how much mercury will be above the mark? $α$ for glass is $10 \times {10^{- 6}}^{\circ} C^{- 1}$ and coefficient of volumetric expansion of mercury is $180 \times {10^{- 6}}^{\circ} C^{- 1}$

Discussion

11.	State whether the potential energy in each of the following cases increases or decreases: a) A spring is compressed. b) A spring is stretched. c) A body is taken away by the force of gravity. d) Air bubble rises up in water.
Answer» State whether the potential energy in each of the following cases increases or decreases: a) A spring is compressed. b) A spring is stretched. c) A body is taken away by the force of gravity. d) Air bubble rises up in water.

Discussion

12.	In a plane E.M. wave, the electric field oscillates sinusoidally at a frequency of 2.5×1010 Hz and amplitude 480 V/m. The amplitude of oscillating magnetic field will be
Answer» In a plane E.M. wave, the electric field oscillates sinusoidally at a frequency of $2.5 \times 10^{10} Hz$ and amplitude $480 V/m$ . The amplitude of oscillating magnetic field will be

Discussion

13.	The wave number of the limiting line of Balmer series of hydrogen spectrum is
Answer» The wave number of the limiting line of Balmer series of hydrogen spectrum is

Discussion

14.	18, If at the moment t-O, the separation between the cars is 90 m and the length of each car is 5 m, theof time at which they completely cross each other is t(1) 1 s(3) 22 s(2) 4 s(4) 3.6 s19. The distance moved hy car P during the timo int
Answer» 18, If at the moment t-O, the separation between the cars is 90 m and the length of each car is 5 m, theof time at which they completely cross each other is t(1) 1 s(3) 22 s(2) 4 s(4) 3.6 s19. The distance moved hy car P during the timo int

Discussion

15.	A uniform semicircular ring having mass m and radius r is hanging at one of its ends freely as shown in the figure. The ring is slightly disturbed so that it oscillates in its own plane. The time period of oscillation of the ring is
Answer» A uniform semicircular ring having mass $m$ and radius $r$ is hanging at one of its ends freely as shown in the figure. The ring is slightly disturbed so that it oscillates in its own plane. The time period of oscillation of the ring is

Discussion

16.	A thin, straight conductor lies along the axis of a hollow conductor of radius R and both carry equal currents in the same direction. The magnetic field B is plotted against the distance r from the axis. Which of the following best represents the resulting curve ?
Answer» A thin, straight conductor lies along the axis of a hollow conductor of radius $R$ and both carry equal currents in the same direction. The magnetic field $B$ is plotted against the distance $r$ from the axis. Which of the following best represents the resulting curve ?

Discussion

17.	18. A solid sphere moves at a terminal velocity of }20m/s in air at a place where }g=9.8m/s^2 . The } sphere is taken in a gravity free hall having air at the same pressure and pushed down at a } speed of }20m/s. (A) Its initial acceleration will be }9.8m/s^2 downward } (B) Its initial acceleration will be }9.8m/s^2 upward} (C) The magnitude of acceleration will decrease as the time passes. } (D)It will eventually stop.
Answer» 18. A solid sphere moves at a terminal velocity of }20m/s in air at a place where }g=9.8m/s^2 . The } sphere is taken in a gravity free hall having air at the same pressure and pushed down at a } speed of }20m/s. (A) Its initial acceleration will be }9.8m/s^2 downward } (B) Its initial acceleration will be }9.8m/s^2 upward} (C) The magnitude of acceleration will decrease as the time passes. } (D)It will eventually stop.

Discussion

18.	For a uniform rectangular sheet shown in the figure, the ratio of moments of inertia about the axes perpendicular to the sheet and passing through O (the centre of mass) and O′ (corner point) is :
Answer» For a uniform rectangular sheet shown in the figure, the ratio of moments of inertia about the axes perpendicular to the sheet and passing through $O$ (the centre of mass) and $O^{'}$ (corner point) is :

Discussion

19.	A parallel plate condenser is filled with two dielectrics as shown.Area of each plate is A m2 and the separation is t m. The dielectric constants are k1 and k2 respectively. Its capacitance in farad will be
Answer» A parallel plate condenser is filled with two dielectrics as shown. Area of each plate is $A$ $m^{2}$ and the separation is $t$ m. The dielectric constants are $k_{1}$ and $k_{2}$ respectively. Its capacitance in farad will be

Discussion

20.	A mass m is revolving in a vertical circle at the end of a string of length 20 cms. By how much does the tension of the string at the lowest point exceed the tension at the topmost point
Answer» A mass $m$ is revolving in a vertical circle at the end of a string of length $20 cms$ . By how much does the tension of the string at the lowest point exceed the tension at the topmost point

Discussion

21.	A transparent cube of 15 cm edge contains a small air bubble. Its apparent depth when viewed through one face is 6 cm and when viewed through opposite face is 4 cm. The refractive index of material of cube is
Answer» A transparent cube of 15 cm edge contains a small air bubble. Its apparent depth when viewed through one face is 6 cm and when viewed through opposite face is 4 cm. The refractive index of material of cube is

Discussion

22.	Four point charges of 1 μC, 2 μC, 3 μC, and 4 μC, are placed along x axis at x = 1 m, x = 2 m, x = 3 m and x = 4 m respectively. The electric field intensity at origin due to first three charges is
Answer» Four point charges of 1 μC, 2 μC, 3 μC, and 4 μC, are placed along x axis at x = 1 m, x = 2 m, x = 3 m and x = 4 m respectively. The electric field intensity at origin due to first three charges is

Discussion

23.	An electron is taken from point A to point B along the path AB in a uniform electric field of intensity E=10 V/m. Side AB=5 m, and side BC=3 m. Then, the amount of external workdone on the electron (in eV) is
Answer» An electron is taken from point $A$ to point $B$ along the path $A B$ in a uniform electric field of intensity $E = 10 V/m$ . Side $A B = 5 m$ , and side $B C = 3 m$ . Then, the amount of external workdone on the electron (in $eV)$ is

Discussion

24.	A synchronous motor improves the power factor of a 300kW load from 0.6 lagging to 0.8 lagging and simultaneously the motor carries a load of 100 kW. The power factor at which the motor operates is ______ 0.7
Answer» A synchronous motor improves the power factor of a 300kW load from 0.6 lagging to 0.8 lagging and simultaneously the motor carries a load of 100 kW. The power factor at which the motor operates is ______ 0.7

Discussion

25.	For a Rocket propulsion velocity of exhaust gases relative to rocket is 2 km/s. If mass of rocket system is 1000 kg, then the rate of fuel consumption for a rocket to rise up with an acceleration 4.9 m/s^2 will be:-1) 12.25 kg/s2) 17.5 kg/s3) 7.35 kg/s4) 5.2 kg/s
Answer» For a Rocket propulsion velocity of exhaust gases relative to rocket is 2 km/s. If mass of rocket system is 1000 kg, then the rate of fuel consumption for a rocket to rise up with an acceleration 4.9 m/s^2 will be:- 1) 12.25 kg/s 2) 17.5 kg/s 3) 7.35 kg/s 4) 5.2 kg/s

Discussion

26.	Four students observed an ideal gas undergoing a change of state from A to B. Their observations are along four different paths shown in the figure below. Their conclusions are as follows: (P) Change in internal energy is same in IV and III cases, but not in I and II (Q) Change in internal energy is same in all the four cases (R) Work done is maximum in case I (S) Workdone is minimum in case II Which option represents correct conclusions drawn by the students?
Answer» Four students observed an ideal gas undergoing a change of state from A to B. Their observations are along four different paths shown in the figure below. Their conclusions are as follows: $(P)$ Change in internal energy is same in $I V$ and $I I I$ cases, but not in $I$ and $I I$ $(Q)$ Change in internal energy is same in all the four cases $(R)$ Work done is maximum in case $I$ $(S)$ Workdone is minimum in case $I I$ Which option represents correct conclusions drawn by the students?

Discussion

27.	-q charge is oscillationg along equatorial plane . two fixed charges are +Q are present on axial plane . calculate time period
Answer» -q charge is oscillationg along equatorial plane . two fixed charges are +Q are present on axial plane . calculate time period

Discussion

28.	What is permittivity?
Answer» What is permittivity?

Discussion

29.	What range force is electromagnetic force?
Answer» What range force is electromagnetic force?

Discussion

30.	Why magnetic Lorentz force cannot change the speed and kinetic energy of charged particle but change the velocity and momentum(only in direction)?
Answer» Why magnetic Lorentz force cannot change the speed and kinetic energy of charged particle but change the velocity and momentum(only in direction)?

Discussion

31.	The CFSE for [CoCl6]4− complex is 18000 cm−1 the Δ for [CoCl4]2− will be
Answer» The CFSE for $[C o C l_{6}]^{4 -}$ complex is 18000 $c m^{- 1}$ the $Δ$ for $[C o C l_{4}]^{2 -}$ will be

Discussion

32.	What is the smallest electric force between two charges placed at a distance of 1 m ?
Answer» What is the smallest electric force between two charges placed at a distance of $1 m$ ?

Discussion

33.	A small body is at a distance r from the centre of Mercury planet, where r is greater than the radius of Mercury. The energy required to shift the body from r to 2r measured from the centre is E. The energy reqiured to shift it from 2r to 3r willl be
Answer» A small body is at a distance $r$ from the centre of Mercury planet, where $r$ is greater than the radius of Mercury. The energy required to shift the body from $r$ to $2 r$ measured from the centre is $E$ . The energy reqiured to shift it from $2 r$ to $3 r$ willl be

Discussion

34.	A wooden block in the form of a uniform cylinder floats with one-third length above the water surface. A small chip of this block is cut and held at rest at the bottom of a container containing water to a height of 1 m and is then released. The time in which it will rise to the surface of water is (g=10 m/s2)
Answer» A wooden block in the form of a uniform cylinder floats with one-third length above the water surface. A small chip of this block is cut and held at rest at the bottom of a container containing water to a height of $1 m$ and is then released. The time in which it will rise to the surface of water is $(g = 10 m / s^{2})$

Discussion

35.	A water tank has three holes A,B and C. The water coming out of the three holes is falling at different distances. Explain.
Answer» A water tank has three holes A,B and C. The water coming out of the three holes is falling at different distances. Explain.

Discussion

36.	an object is placed on the principal axis of a concave mirror of focal length 24 cm. if the image distance is 20 cm more than the object distance then magnification of the image will be
Answer» an object is placed on the principal axis of a concave mirror of focal length 24 cm. if the image distance is 20 cm more than the object distance then magnification of the image will be

Discussion

37.	130.A sphere of radius 4 cm is placed within a hollow sphere of radius 6 cm.the inner sphere is charged to a potential of 3 ESU when the outer sphere is earthed,find the charge on the inner sphere
Answer» 130.A sphere of radius 4 cm is placed within a hollow sphere of radius 6 cm.the inner sphere is charged to a potential of 3 ESU when the outer sphere is earthed,find the charge on the inner sphere

Discussion

38.	A boy of height 1.5 m is moving on a skateboard due east with velocity 4 m/s. He throws a coin vertically upward with a velocity of 3 m/s relative to himself. Find the total displacement of the coin relative to ground till it comes to the hand of the boy. Take g=10 m/s2.
Answer» A boy of height $1.5 m$ is moving on a skateboard due east with velocity $4 m/s$ . He throws a coin vertically upward with a velocity of $3 m/s$ relative to himself. Find the total displacement of the coin relative to ground till it comes to the hand of the boy. Take $g = 10 {m/s}^{2}$ .

Discussion

39.	A ball is thrown vertically upwards with a velocity of 20m/s from a height of 10m above the ground. The elapsed the ball hits the ground is A) (2+ \sqrt6)s B) (2+\sqrt6/2)s C) ( \sqrt6-2)s D) (\sqrt6-2/2)s
Answer» A ball is thrown vertically upwards with a velocity of 20m/s from a height of 10m above the ground. The elapsed the ball hits the ground is A) (2+ \sqrt6)s B) (2+\sqrt6/2)s C) ( \sqrt6-2)s D) (\sqrt6-2/2)s

Discussion

40.	Consider a book lying on a table. The weight of the book and the normal force by the table on the book are equal in magnitude and opposite in direction. Is this an example of Newton's third law?
Answer» Consider a book lying on a table. The weight of the book and the normal force by the table on the book are equal in magnitude and opposite in direction. Is this an example of Newton's third law?

Discussion

41.	A particle having a mass m and velocity Vm=3 m/s in the y-direction is projected on to a horizontal belt that is moving with uniform velocity Vb=4 m/s in the x direction as shown in figure. μ=0.5 is the coefficient of friction between the particle and the belt. Assuming that the particle first touches the belt at the origin of the fixed xy coordinate system and remains on the belt, the coordinates of the point where the sliding stops is (x,y). Then x+y=
Answer» A particle having a mass $m$ and velocity $V_{m} = 3 m / s$ in the y-direction is projected on to a horizontal belt that is moving with uniform velocity $V_{b} = 4 m / s$ in the $x$ direction as shown in figure. $μ = 0.5$ is the coefficient of friction between the particle and the belt. Assuming that the particle first touches the belt at the origin of the fixed xy coordinate system and remains on the belt, the coordinates of the point where the sliding stops is $(x, y)$ . Then $x + y =$

Discussion

42.	A block of mass m is sliding down on a fixed inclined plane with velocity of 2 m/s for a distance of 2 m. Angle of inclined plane is 35∘. Calculate the work done by normal reaction on the block.
Answer» A block of mass $m$ is sliding down on a fixed inclined plane with velocity of $2 m/s$ for a distance of $2 m$ . Angle of inclined plane is $35^{\circ}$ . Calculate the work done by normal reaction on the block.

Discussion

43.	In byjus, in chapter state of matters,In video whose title is The Equation of state, at time 02:26, PV=nRT Formula is not fitting!!! P=3atm V=20 cm³ n=10moles T= 345K Why?
Answer» In byjus, in chapter state of matters,In video whose title is The Equation of state, at time 02:26, PV=nRT Formula is not fitting!!! P=3atm V=20 cm³ n=10moles T= 345K Why?

43.

In byjus, in chapter state of matters,In video whose title is The Equation of state, at time 02:26, PV=nRT Formula is not fitting!!! P=3atm V=20 cm³ n=10moles T= 345K Why?

Answer»

In byjus, in chapter state of matters,In video whose title is The Equation of state, at time 02:26, PV=nRT Formula is not fitting!!!

P=3atm

V=20 cm³

n=10moles

T= 345K

Why?

Discussion

44.	Why do electric field lines have the tendency to contract lengthwise
Answer» Why do electric field lines have the tendency to contract lengthwise

Discussion

45.	The distance between two stars of masses 3MS and 6MS is 9R. Here R is the mean distance between the centers of the Earth and the Sun, and MS is the mass of the Sun. The two stars orbit around their common center of mass in circular orbits with period nT, where T is the period of Earth’s revolution around the Sun. The value of n is
Answer» The distance between two stars of masses $3 M_{S}$ and $6 M_{S}$ is $9 R$ . Here $R$ is the mean distance between the centers of the Earth and the Sun, and $M_{S}$ is the mass of the Sun. The two stars orbit around their common center of mass in circular orbits with period $n T$ , where $T$ is the period of Earth’s revolution around the Sun. The value of $n$ is

Discussion

46.	A thin bar of length L has a mass per unit length λ, that increases linearly with distance form one end. If its total mass is M and its mass per unit legth at the lighter end is λ0, then the distance of the center of mass from the lighter end is:
Answer» A thin bar of length $L$ has a mass per unit length $λ$ , that increases linearly with distance form one end. If its total mass is $M$ and its mass per unit legth at the lighter end is $λ_{0}$ , then the distance of the center of mass from the lighter end is:

Discussion

47.	Uniform electric field of magnitude 100 v/m in space is directed along the line y=3+x. Find the potential difference between point A(3,1) a nd B(1,3)
Answer» Uniform electric field of magnitude 100 v/m in space is directed along the line y=3+x. Find the potential difference between point A(3,1) a nd B(1,3)

Discussion

48.	why partial pressure of a wet gas is greater than dry ga
Answer» why partial pressure of a wet gas is greater than dry ga

Discussion

49.	Figure shows a typical circuit for low-pass filter. An AC input Vi = 10 mV is applied at the left end and the output V0 is received at the right end. Find the output voltages for V = 10 k Hz, 100 kHz, 1.0 MHz and 10.0 MHz. Note that as the frequency is increased the output decreases and hence the name low-pass filter.
Answer» Figure shows a typical circuit for low-pass filter. An AC input $V_{i}$ = 10 mV is applied at the left end and the output $V_{0}$ is received at the right end. Find the output voltages for V = 10 k Hz, 100 kHz, 1.0 MHz and 10.0 MHz. Note that as the frequency is increased the output decreases and hence the name low-pass filter.

49.

Figure shows a typical circuit for low-pass filter. An AC input Vi = 10 mV is applied at the left end and the output V0 is received at the right end. Find the output voltages for V = 10 k Hz, 100 kHz, 1.0 MHz and 10.0 MHz. Note that as the frequency is increased the output decreases and hence the name low-pass filter.

Answer»

Figure shows a typical circuit for low-pass filter. An AC input $V_{i}$ = 10 mV is applied at the left end and the output $V_{0}$ is received at the right end. Find the output voltages for V = 10 k Hz, 100 kHz, 1.0 MHz and 10.0 MHz. Note that as the frequency is increased the output decreases and hence the name low-pass filter.

Discussion

50.	The velocity of kerosene oil in a horizontal pipe is 5 m/s. If then the velocity head of oil will be
Answer» The velocity of kerosene oil in a horizontal pipe is 5 m/s. If then the velocity head of oil will be

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

At room temperature (27.0 °C) the resistance of a heating elementis 100 W. What is the temperature of the element if the resistance isfound to be 117 W, given that the temperature coefficient of thematerial of the resistor is 1.70 × 10–4 °C–1.

In a full wave rectifier circuit operating from 50 Hz mains frequency, the fundamental frequency in the ripple would be

A 2 V battery is connected across the points A and B as shown in the figure given below. Assuming that the resistance of each diode is zero in forward bias and infinity in reverse bias, the current supplied by the battery when its positive terminal is connected to A is

A test tube of cross-sectional area a has some lead shots in it. The total mass is m. It floats upright in liquid of density d. when pushed down little and released, it oscillates up and down with a period T. Use dimensional considerations and choose the correct relationship from the following.

A 13m ladder is placed against a smooth vertical wall with its lower end 5m from the wall. what should be the minimum coefficient of friction between ladder and floor so that it remains in equilibrium.

Two identically charged spheres are suspended by strings of equal length. The strings make an angle of 30 degrees with each other. When suspended in a liquid of density 0.8gm/cc, the angle remains same. What's the dielectric constant of liquid? Density of sphere = 1.6gm/cc.

Consider the common emitter circuit shown in the figure below:If the value of β=99, then the value of the lower 3-dB frequency is ________Hz.(Assume VT=25 mV)7.95

One plate of a capacitor is connected to a spring as shown. Area of both the plates is A and separation is d when capacitor is uncharged. When capacitor is charged in steady state separation between the plate is 0.8d the force constant of the spring is

A glass flask is filled upto a mark with 50 cm3 of mercury at 18∘C. If the flask and contents are heated to 38∘C, how much mercury will be above the mark?α for glass is 10×10−6∘C−1 and coefficient of volumetric expansion of mercury is 180×10−6∘C−1

State whether the potential energy in each of the following cases increases or decreases: a) A spring is compressed. b) A spring is stretched. c) A body is taken away by the force of gravity. d) Air bubble rises up in water.

In a plane E.M. wave, the electric field oscillates sinusoidally at a frequency of 2.5×1010 Hz and amplitude 480 V/m. The amplitude of oscillating magnetic field will be

The wave number of the limiting line of Balmer series of hydrogen spectrum is

18, If at the moment t-O, the separation between the cars is 90 m and the length of each car is 5 m, theof time at which they completely cross each other is t(1) 1 s(3) 22 s(2) 4 s(4) 3.6 s19. The distance moved hy car P during the timo int

A uniform semicircular ring having mass m and radius r is hanging at one of its ends freely as shown in the figure. The ring is slightly disturbed so that it oscillates in its own plane. The time period of oscillation of the ring is

A thin, straight conductor lies along the axis of a hollow conductor of radius R and both carry equal currents in the same direction. The magnetic field B is plotted against the distance r from the axis. Which of the following best represents the resulting curve ?

For a uniform rectangular sheet shown in the figure, the ratio of moments of inertia about the axes perpendicular to the sheet and passing through O (the centre of mass) and O′ (corner point) is :

A parallel plate condenser is filled with two dielectrics as shown.Area of each plate is A m2 and the separation is t m. The dielectric constants are k1 and k2 respectively. Its capacitance in farad will be

A mass m is revolving in a vertical circle at the end of a string of length 20 cms. By how much does the tension of the string at the lowest point exceed the tension at the topmost point

A transparent cube of 15 cm edge contains a small air bubble. Its apparent depth when viewed through one face is 6 cm and when viewed through opposite face is 4 cm. The refractive index of material of cube is

Four point charges of 1 μC, 2 μC, 3 μC, and 4 μC, are placed along x axis at x = 1 m, x = 2 m, x = 3 m and x = 4 m respectively. The electric field intensity at origin due to first three charges is

An electron is taken from point A to point B along the path AB in a uniform electric field of intensity E=10 V/m. Side AB=5 m, and side BC=3 m. Then, the amount of external workdone on the electron (in eV) is

A synchronous motor improves the power factor of a 300kW load from 0.6 lagging to 0.8 lagging and simultaneously the motor carries a load of 100 kW. The power factor at which the motor operates is ______ 0.7

For a Rocket propulsion velocity of exhaust gases relative to rocket is 2 km/s. If mass of rocket system is 1000 kg, then the rate of fuel consumption for a rocket to rise up with an acceleration 4.9 m/s^2 will be:-1) 12.25 kg/s2) 17.5 kg/s3) 7.35 kg/s4) 5.2 kg/s

-q charge is oscillationg along equatorial plane . two fixed charges are +Q are present on axial plane . calculate time period

What is permittivity?

What range force is electromagnetic force?

Why magnetic Lorentz force cannot change the speed and kinetic energy of charged particle but change the velocity and momentum(only in direction)?

The CFSE for [CoCl6]4− complex is 18000 cm−1 the Δ for [CoCl4]2− will be

What is the smallest electric force between two charges placed at a distance of 1 m ?

A small body is at a distance r from the centre of Mercury planet, where r is greater than the radius of Mercury. The energy required to shift the body from r to 2r measured from the centre is E. The energy reqiured to shift it from 2r to 3r willl be

A water tank has three holes A,B and C. The water coming out of the three holes is falling at different distances. Explain.

an object is placed on the principal axis of a concave mirror of focal length 24 cm. if the image distance is 20 cm more than the object distance then magnification of the image will be

130.A sphere of radius 4 cm is placed within a hollow sphere of radius 6 cm.the inner sphere is charged to a potential of 3 ESU when the outer sphere is earthed,find the charge on the inner sphere

A boy of height 1.5 m is moving on a skateboard due east with velocity 4 m/s. He throws a coin vertically upward with a velocity of 3 m/s relative to himself. Find the total displacement of the coin relative to ground till it comes to the hand of the boy. Take g=10 m/s2.

A ball is thrown vertically upwards with a velocity of 20m/s from a height of 10m above the ground. The elapsed the ball hits the ground is A) (2+ \sqrt6)s B) (2+\sqrt6/2)s C) ( \sqrt6-2)s D) (\sqrt6-2/2)s

Consider a book lying on a table. The weight of the book and the normal force by the table on the book are equal in magnitude and opposite in direction. Is this an example of Newton's third law?

A block of mass m is sliding down on a fixed inclined plane with velocity of 2 m/s for a distance of 2 m. Angle of inclined plane is 35∘. Calculate the work done by normal reaction on the block.

In byjus, in chapter state of matters,In video whose title is The Equation of state, at time 02:26, PV=nRT Formula is not fitting!!! P=3atm V=20 cm³ n=10moles T= 345K Why?

Why do electric field lines have the tendency to contract lengthwise

A thin bar of length L has a mass per unit length λ, that increases linearly with distance form one end. If its total mass is M and its mass per unit legth at the lighter end is λ0, then the distance of the center of mass from the lighter end is:

Uniform electric field of magnitude 100 v/m in space is directed along the line y=3+x. Find the potential difference between point A(3,1) a nd B(1,3)

why partial pressure of a wet gas is greater than dry ga

The velocity of kerosene oil in a horizontal pipe is 5 m/s. If then the velocity head of oil will be