50278 + Interview Questions in Physics Page 277 InterviewSolution

13801.	Cos3x
Answer» Cos 3x

Discussion

13802.	A simple pendulum of length 5 m is suspended from the ceiling of a cart. Cart is sliding down on an frictionless surface having angle of inclination 60°. The time period of the pendulum is
Answer» A simple pendulum of length 5 m is suspended from the ceiling of a cart. Cart is sliding down on an frictionless surface having angle of inclination 60°. The time period of the pendulum is

Discussion

13803.	Four equal charges Q are placed at the four corners ofsquare of each side is a. Work done in removing a charge-Q from its centre to infinity is
Answer» Four equal charges Q are placed at the four corners ofsquare of each side is a. Work done in removing a charge-Q from its centre to infinity is

Discussion

13804.	Between two wavelengths 500 A∘ and 1000A∘, aλ is the absorptive power and eλ is the emissive power of a body. If Eλ is the emissive power of a perfectly black body then according to Kirchhoff's law,
Answer» Between two wavelengths $500 A^{\circ}$ and $1000 A^{\circ}, a_{λ}$ is the absorptive power and $e_{λ}$ is the emissive power of a body. If $E_{λ}$ is the emissive power of a perfectly black body then according to Kirchhoff's law,

Discussion

13805.	A tank is filled with a liquid ofdensity rho upto height H`the average pressure on the walls of the container
Answer» A tank is filled with a liquid of density rho upto height H`the average pressure on the walls of the container

Discussion

13806.	A bock of mass m is placed on a frictionless inclined plane of inclination θ. The inclined plane has its base fixed on the floor of a lift which is going up with a constant acceleration a. When the block is released, it will slide down the plane with acceleration
Answer» A bock of mass $m$ is placed on a frictionless inclined plane of inclination $θ$ . The inclined plane has its base fixed on the floor of a lift which is going up with a constant acceleration $a$ . When the block is released, it will slide down the plane with acceleration

Discussion

13807.	Find the ratio of the tension T1 and T2 in the string as shown in the figure. Take g=10 m/s2.
Answer» Find the ratio of the tension $T_{1}$ and $T_{2}$ in the string as shown in the figure. Take $g = 10 {m/s}^{2}$ .

Discussion

13808.	on a horizontal surface of a truck a block of mass 1 kg is placed (u=.6) and truck is moving with an acceleration 5 metre per second square then the frictional force on the block will be5N6N5.88N8N
Answer» on a horizontal surface of a truck a block of mass 1 kg is placed (u=.6) and truck is moving with an acceleration 5 metre per second square then the frictional force on the block will be 5N 6N 5.88N 8N

Discussion

13809.	The magnitude of the resultant of two forces each having magnitude F0 and angle between them is 120o, is xF. Then x is
Answer» The magnitude of the resultant of two forces each having magnitude $F_{0}$ and angle between them is $120^{o},$ is $x F .$ Then $x$ is

Discussion

13810.	a concave mirror of focal length f produces an imae n times the size of object .if the image is real then the dis†an ce of the object from the mirror is
Answer» a concave mirror of focal length f produces an imae n times the size of object .if the image is real then the dis†an ce of the object from the mirror is

Discussion

13811.	A particle A is projected with an initial velocity of 60 m/s at an angle 30∘ to the horizontal. At the same time, a second particle B is projected at an angle α to the horizontal with an initial speed of 50 m/s from a point at a distance of 100 m from A as shown in the figure. If the particles collide in the air, find the angle of projection α of particle B.
Answer» A particle $A$ is projected with an initial velocity of $60 m / s$ at an angle $30^{\circ}$ to the horizontal. At the same time, a second particle $B$ is projected at an angle $α$ to the horizontal with an initial speed of $50 m / s$ from a point at a distance of $100 m$ from $A$ as shown in the figure. If the particles collide in the air, find the angle of projection $α$ of particle $B$ .

Discussion

13812.	The stopping potential for photo-electrons ejected from a surface is 4.5 V when 155 nm photon is incident on the surface. Calculate the stopping potential when 248 nm photon is incident on the surface. (Use hc=1240 eV nm)
Answer» The stopping potential for photo-electrons ejected from a surface is $4.5 V$ when $155 nm$ photon is incident on the surface. Calculate the stopping potential when $248 nm$ photon is incident on the surface. $(Use h c = 1240 eV nm)$

Discussion

13813.	If the frequency of a pendulum of mass m0 is f, then the frequency of a pendulum of mass 4m0 will be (all other conditions remain same).
Answer» If the frequency of a pendulum of mass $m_{0}$ is $f$ , then the frequency of a pendulum of mass $4 m_{0}$ will be (all other conditions remain same).

Discussion

13814.	A rigid body rotates about a stationary axis with an angular retardation α=4√ω, where ω is the angular speed of the body. Find the time after which the body will come to rest, if initially it was rotating at an angular speed of 9 rad/sec.
Answer» A rigid body rotates about a stationary axis with an angular retardation $α = 4 \sqrt{ω}$ , where $ω$ is the angular speed of the body. Find the time after which the body will come to rest, if initially it was rotating at an angular speed of 9 rad/sec.

Discussion

13815.	From a uniform circular disc of radius R and mass 9M, a small disc of radius R3 is removed as shown in the figure. The moment of inertia of the remaining disc about an axis perpendicular to the plane of the disc and passing through centre of disc is
Answer» From a uniform circular disc of radius $R$ and mass $9 M,$ a small disc of radius $\frac{R}{3}$ is removed as shown in the figure. The moment of inertia of the remaining disc about an axis perpendicular to the plane of the disc and passing through centre of disc is

Discussion

13816.	Find the elastic potential energy stored in each spring shown in figure (12-E8), when the block is in equilibrium. Also find the time period of vertical oscillation of the block.
Answer» Find the elastic potential energy stored in each spring shown in figure (12-E8), when the block is in equilibrium. Also find the time period of vertical oscillation of the block.

13816.

Find the elastic potential energy stored in each spring shown in figure (12-E8), when the block is in equilibrium. Also find the time period of vertical oscillation of the block.

Answer»

Find the elastic potential energy stored in each spring shown in figure (12-E8), when the block is in equilibrium. Also find the time period of vertical oscillation of the block.

Discussion

13817.	A boat is moving with a velocity of 3^i+4^j with respect to the ground. The water in the river is moving with a velocity of −3^i−4^j with respect to the ground. The relative velocity of the boat with respect to water is
Answer» A boat is moving with a velocity of $3^i + 4^j$ with respect to the ground. The water in the river is moving with a velocity of $- 3^i - 4^j$ with respect to the ground. The relative velocity of the boat with respect to water is

Discussion

13818.	If ∫sinx⋅ln(sinx) dx=acosx(1−ln(sinx))+ln\|tan(bx)\|+C, then the value of ab is equal to
Answer» If $\int sin x \cdot ln (sin x) d x = a cos x (1 - ln (sin x)) + ln \| tan (b x) \| + C,$ then the value of $\frac{a}{b}$ is equal to

Discussion

13819.	When a object is pushed with a force less than the frictional force. what happens to the object.pls kindly answer y questions
Answer» When a object is pushed with a force less than the frictional force. what happens to the object.pls kindly answer y questions

Discussion

13820.	What is tension in ring due to it's own charge ?
Answer» What is tension in ring due to it's own charge ?

Discussion

13821.	A milliammeter of range 10 mA and resistance 9 Ω is joined in a circuit as shown. The meter gives full scale deflection for current I when A and B are used as its terminals. i.e., current enters at A and leaves at B (C is left isolated). The value of I is
Answer» A milliammeter of range $10 mA$ and resistance $9 Ω$ is joined in a circuit as shown. The meter gives full scale deflection for current $I$ when $A$ and $B$ are used as its terminals. i.e., current enters at $A$ and leaves at $B$ ( $C$ is left isolated). The value of $I$ is

Discussion

13822.	The volume of a gas at 0^°c and 700 mm of Hg pressure is 760 cc. The number of molecules present in this volume is :
Answer» The volume of a gas at 0^°c and 700 mm of Hg pressure is 760 cc. The number of molecules present in this volume is :

Discussion

13823.	A boy in your class has a mass of 40 kg. What is his weight in Newton?
Answer» A boy in your class has a mass of 40 kg. What is his weight in Newton?

Discussion

13824.	A particle executes SHM with a frequency f. the frequency with which it KE oscillates is? 1) f/2 2) f. 3) 2f. 4) 4f
Answer» A particle executes SHM with a frequency f. the frequency with which it KE oscillates is? 1) f/2 2) f. 3) 2f. 4) 4f

Discussion

13825.	Two pith balls carrying equal charges are suspendedfrom a common point by strings of equal length, theequilibrium separation between them is r. Now thestrings are rigidly clamped at half the height. Theequilibrium separation between the balls now become0孁ㄧ寵尊㈱諧竊㈱“1驉套1糊爺章載莓■u宿■顱員y/2
Answer» Two pith balls carrying equal charges are suspendedfrom a common point by strings of equal length, theequilibrium separation between them is r. Now thestrings are rigidly clamped at half the height. Theequilibrium separation between the balls now become0孁ㄧ寵尊㈱諧竊㈱“1驉套1糊爺章載莓■u宿■顱員y/2

Discussion

13826.	a concave mirror of radius of curvature 40cm produces a real image five times the size of object the distance between object and its image is
Answer» a concave mirror of radius of curvature 40cm produces a real image five times the size of object the distance between object and its image is

Discussion

13827.	What is Newton's Rule ?
Answer» What is Newton's Rule ?

Discussion

13828.	Find the derivative of (px+q)(rx+s) where p,q,r and s are fixed non-zero constants.
Answer» Find the derivative of $(p x + q) (\frac{r}{x} + s)$ where $p, q, r$ and $s$ are fixed non-zero constants.

Discussion

13829.	What is bohr frequency rule formula
Answer» What is bohr frequency rule formula

Discussion

13830.	A 12 m long vibrating string has the speed of wave 48 m/s To what frequency it will resonate
Answer» A 12 m long vibrating string has the speed of wave 48 m/s To what frequency it will resonate

Discussion

13831.	A ball is going vertically upwards with a velocity of 12 m/s. When it is 65 m above the ground, a stone is gently from it.The time taken by the stone to reach the ground is (g = 10 m/s2) (a) 13s (b) 6.5s (c) 5.0 s (d) 3.5 s
Answer» A ball is going vertically upwards with a velocity of 12 m/s. When it is 65 m above the ground, a stone is gently from it.The time taken by the stone to reach the ground is (g = 10 m/s2) (a) 13s (b) 6.5s (c) 5.0 s (d) 3.5 s

Discussion

13832.	24. When a 100 ohm resistance is connected to an electric cell , voltmeter reading is 2 V .when the cell is connected to 15 ohm resistance, a ammeter with 1 ohm resistance has reading 0.1 A .Calculate EMF of the cell.
Answer» 24. When a 100 ohm resistance is connected to an electric cell , voltmeter reading is 2 V .when the cell is connected to 15 ohm resistance, a ammeter with 1 ohm resistance has reading 0.1 A .Calculate EMF of the cell.

Discussion

13833.	The static deflection of a spring under gravity, when a mass of 1 kg is suspended from it, is 1 mm. Assume the acceleration due to gravity g = 10 m/s2. The natural frequency of this spring-mass system (in rad/s) is
Answer» The static deflection of a spring under gravity, when a mass of 1 kg is suspended from it, is 1 mm. Assume the acceleration due to gravity g = 10 m/s $^{2}$ . The natural frequency of this spring-mass system (in rad/s) is

Discussion

13834.	How to aplly w .e thn?
Answer» How to aplly w .e thn?

Discussion

13835.	129.When an object is in motion in a vertical circle its tension at the lowest point is
Answer» 129.When an object is in motion in a vertical circle its tension at the lowest point is

Discussion

13836.	A football is kicked 20m/s at a projection angle of 45°. A receiver on the goal line 25 m away in the direction of the kick runs the same instant to meet the ball. What must be his speed, if he is to catch the ball before it hits the ground??
Answer» A football is kicked 20m/s at a projection angle of 45°. A receiver on the goal line 25 m away in the direction of the kick runs the same instant to meet the ball. What must be his speed, if he is to catch the ball before it hits the ground??

Discussion

13837.	When a charged particle is fired with a velocity in a region containing both electric field and magnetic field , it is not deflected from its straight line trajectory. Hence Options: B x v =E v X B =
Answer» When a charged particle is fired with a velocity in a region containing both electric field and magnetic field , it is not deflected from its straight line trajectory. Hence Options: B x v =E v X B =

Discussion

13838.	A particle is given an initial speed u inside a smooth spherical shell of radius r such that it is just able to complete the circle. Acceleration of the particle at point B is
Answer» A particle is given an initial speed $u$ inside a smooth spherical shell of radius $r$ such that it is just able to complete the circle. Acceleration of the particle at point B is

Discussion

13839.	A small bob tied at one end of a thin string of length 1 m is describing a vertical circle so that the maximum and minimum tension in the string are in the ratio 5:1. The velocity of the bob at the highest position is ______m/s.(Take g=10 m/s2)
Answer» A small bob tied at one end of a thin string of length $1 m$ is describing a vertical circle so that the maximum and minimum tension in the string are in the ratio $5 : 1$ . The velocity of the bob at the highest position is ______ $m/s$ . $($ Take $g = 10 {m/s}^{2})$

Discussion

13840.	21. A piece of wire of resistance R is cut into n equalparts. These parts are then connected in parallel.If the equivalent resistance of parallel combinationis R, thenISisR'
Answer» 21. A piece of wire of resistance R is cut into n equalparts. These parts are then connected in parallel.If the equivalent resistance of parallel combinationis R, thenISisR'

Discussion

13841.	A block of mass 10 kg is placed on rough inclinedplane of inclination angle 37. Coefficient of frictionbetween block & plane is 0.8, find minimummagnitude of F so that block remains at rest.
Answer» A block of mass 10 kg is placed on rough inclinedplane of inclination angle 37. Coefficient of frictionbetween block & plane is 0.8, find minimummagnitude of F so that block remains at rest.

Discussion

13842.	A cylindrical cacity of diameter a exists inside a cylinder of diameter 2a as shown in the figure. Both the cylinder and the cavity are infinitely long. A uniform current density J flows along the length. If the magnitude of the magnetic field at the point P is given by N12μ0aJ, then the value of N isDiagram
Answer» A cylindrical cacity of diameter $a$ exists inside a cylinder of diameter $2 a$ as shown in the figure. Both the cylinder and the cavity are infinitely long. A uniform current density $J$ flows along the length. If the magnitude of the magnetic field at the point $P$ is given by $\frac{N}{12} μ_{0} a J$ , then the value of $N$ is Diagram

Discussion

13843.	Obtain the binding energy of the nuclei 5626Fe and 20983 Bi in units ofMeV from the following data:m (5626Fe ) = 55.934939 u m ( 20983 Bi ) = 208.980388 u
Answer» Obtain the binding energy of the nuclei 5626Fe and 20983 Bi in units ofMeV from the following data:m (5626Fe ) = 55.934939 u m ( 20983 Bi ) = 208.980388 u

Discussion

13844.	The frequency of revolution of electron in nth Bohr orbit is Vn. The graph between log n and log(VnV1) may be
Answer» The frequency of revolution of electron in $n^{t h}$ Bohr orbit is $V_{n}$ . The graph between $l o g n$ and $l o g (\frac{V_{n}}{V_{1}})$ may be

Discussion

13845.	A metallic block carrying current I is subjected to a uniform magnetic field →B as shown in the figure. The moving charges experience a force →F given by ........... which results in the lowering of the potential of the face ........ Assume the speed of the carriers to be v
Answer» A metallic block carrying current I is subjected to a uniform magnetic field $\to B$ as shown in the figure. The moving charges experience a force $\to F$ given by ........... which results in the lowering of the potential of the face ........ Assume the speed of the carriers to be v

Discussion

13846.	Two satellite s1 and s2 revolve round a planet in coplanar circular orbits in the same sense. Their period of revolution are 1 hour and 8 hours respectively. The radii of orbit of s1 is 10^ 4 km. When s2 is closest to s1, the angular speed of s2 as actually observed by an astronaut in s1
Answer» Two satellite s1 and s2 revolve round a planet in coplanar circular orbits in the same sense. Their period of revolution are 1 hour and 8 hours respectively. The radii of orbit of s1 is 10^ 4 km. When s2 is closest to s1, the angular speed of s2 as actually observed by an astronaut in s1

Discussion

13847.	Figure 10.24 (a) shows a thin liquid film supporting a small weight = 4.5×10–2N. What is the weight supported by a film of the same liquid at the same temperature in Fig. (b) and (c)? Explain your answer physically.
Answer» Figure 10.24 (a) shows a thin liquid film supporting a small weight = $4.5 \times 10^{- 2} N$ . What is the weight supported by a film of the same liquid at the same temperature in Fig. (b) and (c)? Explain your answer physically.

Discussion

13848.	Are the dimensions of velocity and speed are same?
Answer» Are the dimensions of velocity and speed are same?

Discussion

13849.	A body is projected from the top of a tower of height 32 m with a velocity of 20 m/s at an angle of 37∘ above the horizontal. Find the horizontal distance travelled before it hits the ground. (Take g=10 m/s2)
Answer» A body is projected from the top of a tower of height $32 m$ with a velocity of $20 m/s$ at an angle of $37^{\circ}$ above the horizontal. Find the horizontal distance travelled before it hits the ground. (Take $g = 10 m / s^{2}$ )

Discussion

13850.	A body of mass 2 kg is attached to a light rod of length 5 m and is allowed to move in a vertical circle. The body is given an initial velocity of u m/s at the bottom-most point, such that the final velocity at the top-most point is zero. The value of u is(Take g=10 m/s2)
Answer» A body of mass $2 kg$ is attached to a light rod of length $5 m$ and is allowed to move in a vertical circle. The body is given an initial velocity of $u m/s$ at the bottom-most point, such that the final velocity at the top-most point is zero. The value of $u$ is $($ Take $g = 10 {m/s}^{2})$

Discussion

Explore topic-wise InterviewSolutions in .

Cos3x

A simple pendulum of length 5 m is suspended from the ceiling of a cart. Cart is sliding down on an frictionless surface having angle of inclination 60°. The time period of the pendulum is

Four equal charges Q are placed at the four corners ofsquare of each side is a. Work done in removing a charge-Q from its centre to infinity is

Between two wavelengths 500 A∘ and 1000A∘, aλ is the absorptive power and eλ is the emissive power of a body. If Eλ is the emissive power of a perfectly black body then according to Kirchhoff's law,

A tank is filled with a liquid ofdensity rho upto height H`the average pressure on the walls of the container

A bock of mass m is placed on a frictionless inclined plane of inclination θ. The inclined plane has its base fixed on the floor of a lift which is going up with a constant acceleration a. When the block is released, it will slide down the plane with acceleration

Find the ratio of the tension T1 and T2 in the string as shown in the figure. Take g=10 m/s2.

on a horizontal surface of a truck a block of mass 1 kg is placed (u=.6) and truck is moving with an acceleration 5 metre per second square then the frictional force on the block will be5N6N5.88N8N

The magnitude of the resultant of two forces each having magnitude F0 and angle between them is 120o, is xF. Then x is

a concave mirror of focal length f produces an imae n times the size of object .if the image is real then the dis†an ce of the object from the mirror is

The stopping potential for photo-electrons ejected from a surface is 4.5 V when 155 nm photon is incident on the surface. Calculate the stopping potential when 248 nm photon is incident on the surface. (Use hc=1240 eV nm)

If the frequency of a pendulum of mass m0 is f, then the frequency of a pendulum of mass 4m0 will be (all other conditions remain same).

A rigid body rotates about a stationary axis with an angular retardation α=4√ω, where ω is the angular speed of the body. Find the time after which the body will come to rest, if initially it was rotating at an angular speed of 9 rad/sec.

From a uniform circular disc of radius R and mass 9M, a small disc of radius R3 is removed as shown in the figure. The moment of inertia of the remaining disc about an axis perpendicular to the plane of the disc and passing through centre of disc is

Find the elastic potential energy stored in each spring shown in figure (12-E8), when the block is in equilibrium. Also find the time period of vertical oscillation of the block.

A boat is moving with a velocity of 3^i+4^j with respect to the ground. The water in the river is moving with a velocity of −3^i−4^j with respect to the ground. The relative velocity of the boat with respect to water is

If ∫sinx⋅ln(sinx) dx=acosx(1−ln(sinx))+ln|tan(bx)|+C, then the value of ab is equal to

When a object is pushed with a force less than the frictional force. what happens to the object.pls kindly answer y questions

What is tension in ring due to it's own charge ?

A milliammeter of range 10 mA and resistance 9 Ω is joined in a circuit as shown. The meter gives full scale deflection for current I when A and B are used as its terminals. i.e., current enters at A and leaves at B (C is left isolated). The value of I is

The volume of a gas at 0^°c and 700 mm of Hg pressure is 760 cc. The number of molecules present in this volume is :

A boy in your class has a mass of 40 kg. What is his weight in Newton?

A particle executes SHM with a frequency f. the frequency with which it KE oscillates is? 1) f/2 2) f. 3) 2f. 4) 4f

a concave mirror of radius of curvature 40cm produces a real image five times the size of object the distance between object and its image is

What is Newton's Rule ?

Find the derivative of (px+q)(rx+s) where p,q,r and s are fixed non-zero constants.

What is bohr frequency rule formula

A 12 m long vibrating string has the speed of wave 48 m/s To what frequency it will resonate

A ball is going vertically upwards with a velocity of 12 m/s. When it is 65 m above the ground, a stone is gently from it.The time taken by the stone to reach the ground is (g = 10 m/s2) (a) 13s (b) 6.5s (c) 5.0 s (d) 3.5 s

24. When a 100 ohm resistance is connected to an electric cell , voltmeter reading is 2 V .when the cell is connected to 15 ohm resistance, a ammeter with 1 ohm resistance has reading 0.1 A .Calculate EMF of the cell.

The static deflection of a spring under gravity, when a mass of 1 kg is suspended from it, is 1 mm. Assume the acceleration due to gravity g = 10 m/s2. The natural frequency of this spring-mass system (in rad/s) is

How to aplly w .e thn?

129.When an object is in motion in a vertical circle its tension at the lowest point is

A football is kicked 20m/s at a projection angle of 45°. A receiver on the goal line 25 m away in the direction of the kick runs the same instant to meet the ball. What must be his speed, if he is to catch the ball before it hits the ground??

When a charged particle is fired with a velocity in a region containing both electric field and magnetic field , it is not deflected from its straight line trajectory. Hence Options: B x v =E v X B =

A particle is given an initial speed u inside a smooth spherical shell of radius r such that it is just able to complete the circle. Acceleration of the particle at point B is

A small bob tied at one end of a thin string of length 1 m is describing a vertical circle so that the maximum and minimum tension in the string are in the ratio 5:1. The velocity of the bob at the highest position is ______m/s.(Take g=10 m/s2)

21. A piece of wire of resistance R is cut into n equalparts. These parts are then connected in parallel.If the equivalent resistance of parallel combinationis R, thenISisR'

A block of mass 10 kg is placed on rough inclinedplane of inclination angle 37. Coefficient of frictionbetween block & plane is 0.8, find minimummagnitude of F so that block remains at rest.

Obtain the binding energy of the nuclei 5626Fe and 20983 Bi in units ofMeV from the following data:m (5626Fe ) = 55.934939 u m ( 20983 Bi ) = 208.980388 u

The frequency of revolution of electron in nth Bohr orbit is Vn. The graph between log n and log(VnV1) may be

A metallic block carrying current I is subjected to a uniform magnetic field →B as shown in the figure. The moving charges experience a force →F given by ........... which results in the lowering of the potential of the face ........ Assume the speed of the carriers to be v

Two satellite s1 and s2 revolve round a planet in coplanar circular orbits in the same sense. Their period of revolution are 1 hour and 8 hours respectively. The radii of orbit of s1 is 10^ 4 km. When s2 is closest to s1, the angular speed of s2 as actually observed by an astronaut in s1

Figure 10.24 (a) shows a thin liquid film supporting a small weight = 4.5×10–2N. What is the weight supported by a film of the same liquid at the same temperature in Fig. (b) and (c)? Explain your answer physically.

Are the dimensions of velocity and speed are same?

A body is projected from the top of a tower of height 32 m with a velocity of 20 m/s at an angle of 37∘ above the horizontal. Find the horizontal distance travelled before it hits the ground. (Take g=10 m/s2)

A body of mass 2 kg is attached to a light rod of length 5 m and is allowed to move in a vertical circle. The body is given an initial velocity of u m/s at the bottom-most point, such that the final velocity at the top-most point is zero. The value of u is(Take g=10 m/s2)