50278 + Interview Questions in Physics

1.	The anode voltage of a photocell is kept fixed. The wavelength λ of the light falling on the cathode is gradually changed. The plate current I of the photocell varies with λ as follows :
Answer» The anode voltage of a photocell is kept fixed. The wavelength $λ$ of the light falling on the cathode is gradually changed. The plate current $I$ of the photocell varies with $λ$ as follows :

Discussion

2.	A vertical wire kept in xz-plane carries a current from Q to P as shown in figure. The magnetic field due to current will have the direction at the origin O along
Answer» A vertical wire kept in $x z$ -plane carries a current from $Q$ to $P$ as shown in figure. The magnetic field due to current will have the direction at the origin $O$ along

Discussion

3.	A gas is suddenly compressed to 1/4th of its original volume.what will be the rise in temperature if it's initial temperature is27°C(given adiabatic constant=1.5)
Answer» A gas is suddenly compressed to 1/4th of its original volume.what will be the rise in temperature if it's initial temperature is27°C(given adiabatic constant=1.5)

Discussion

4.	A rod of length 1 m rotates in the xy plane about the fixed point O in the anticlockwise sense, as shown in figure, with angular velocity ω=a+bt where a=10 rad s−1 and b=5 rad s−2. The velocity and acceleration of the point A at t=0 is
Answer» A rod of length $1 m$ rotates in the $x y$ plane about the fixed point $O$ in the anticlockwise sense, as shown in figure, with angular velocity $ω = a + b t$ where $a = 10 {rad s}^{- 1}$ and $b = 5 {rad s}^{- 2}$ . The velocity and acceleration of the point $A$ at $t = 0$ is

Discussion

5.	Consider the discrete time signalx(n)=(13)nu(n),whereu(n)={1,n≥00,n<0and y(n)=x(−n), −∞<n<∞Then ∞∑n=−∞y(n) is______.1.5
Answer» Consider the discrete time signal $x (n) = {(\frac{1}{3})}^{n} u (n), w h e r e u (n) = {\begin{matrix} 1, & n \geq 0 0, & n < 0 \end{matrix}$ and $y (n) = x (- n), - \infty < n < \infty$ Then $\infty \sum n = - \infty y (n)$ is______. 1.5

Discussion

6.	Two plane mirrors M1 and M2 each have length 1 m and are separated by 1 cm. A ray of light is incident on one end of mirror M1 at an angle of 45∘. How many reflections will the ray have before going out from the other end?
Answer» Two plane mirrors $M_{1}$ and $M_{2}$ each have length $1 m$ and are separated by $1 cm$ . A ray of light is incident on one end of mirror $M_{1}$ at an angle of $45^{\circ}$ . How many reflections will the ray have before going out from the other end?

Discussion

7.	what is meant by an impact time and how to calculate it ?
Answer» what is meant by an impact time and how to calculate it ?

Discussion

8.	A conducting square loop of side L and resistance R moves in its plane with a uniform velocity v perpendicular to one of its sides. It is sorrounded by a magnetic field B which is constant in time and space and is pointing perpendicularly into the plane of the loop. The current induced in the loop is
Answer» A conducting square loop of side L and resistance R moves in its plane with a uniform velocity $v$ perpendicular to one of its sides. It is sorrounded by a magnetic field B which is constant in time and space and is pointing perpendicularly into the plane of the loop. The current induced in the loop is

8.

A conducting square loop of side L and resistance R moves in its plane with a uniform velocity v perpendicular to one of its sides. It is sorrounded by a magnetic field B which is constant in time and space and is pointing perpendicularly into the plane of the loop. The current induced in the loop is

Answer»

A conducting square loop of side L and resistance R moves in its plane with a uniform velocity $v$ perpendicular to one of its sides. It is sorrounded by a magnetic field B which is constant in time and space and is pointing perpendicularly into the plane of the loop. The current induced in the loop is

Discussion

9.	Monochromatic light is incident on a glass prism of angle A. If the refractive index of the material of the prism is μ, a ray incident at an angle θ, on the face AB would get transmitted through the face AC of the prism, provided
Answer» Monochromatic light is incident on a glass prism of angle A. If the refractive index of the material of the prism is $μ$ , a ray incident at an angle $θ$ , on the face AB would get transmitted through the face AC of the prism, provided

Discussion

10.	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

11.	Two particles having same time period, same amplitude,same mean position and their shadows are oscilating on the same straight line, are moving such that at T=0 one is at the mean position , and other is at the extreme position. 1. Calculate the time when they will of cross each other . 2. Calculate their maximum separation.3. Calculate the time when they will have maximum separation
Answer» Two particles having same time period, same amplitude,same mean position and their shadows are oscilating on the same straight line, are moving such that at T=0 one is at the mean position , and other is at the extreme position. 1. Calculate the time when they will of cross each other . 2. Calculate their maximum separation. 3. Calculate the time when they will have maximum separation

Discussion

12.	27. When speed of a dc motor increases, the armature current(1) Increases(2) Decreases(3)Does not change(4) Increases and decreases continuously
Answer» 27. When speed of a dc motor increases, the armature current(1) Increases(2) Decreases(3)Does not change(4) Increases and decreases continuously

Discussion

13.	A trolley of mass 300 kg carrying a sandbag of 25 kg is moving uniformly with a speed of 27 km/h on a frictionless track. After a while, sand starts leaking out of a hole on the floor of the trolley at the rate of 0.05 kg s¯¹. What is the speed of the trolley after the entire sand bag is empty ?
Answer» A trolley of mass 300 kg carrying a sandbag of 25 kg is moving uniformly with a speed of 27 km/h on a frictionless track. After a while, sand starts leaking out of a hole on the floor of the trolley at the rate of 0.05 kg s¯¹. What is the speed of the trolley after the entire sand bag is empty ?

Discussion

14.	A ball of mass m=2 kg is travelling under the influence of gravity. At height H=5 m speed of ball is u=10 m/s as shown in figure. Find the torque due to gravity about x axis.
Answer» A ball of mass $m = 2 kg$ is travelling under the influence of gravity. At height $H = 5 m$ speed of ball is $u = 10 m/s$ as shown in figure. Find the torque due to gravity about $x$ axis.

Discussion

15.	The work done in increasing the length of a 1 m long wire of cross-sectional area 1 mm2 through 1 mm will be [Given, Y=2×1011 N/m2]
Answer» The work done in increasing the length of a $1 m$ long wire of cross-sectional area $1 {mm}^{2}$ through $1 mm$ will be [Given, $Y = 2 \times 10^{11} {N/m}^{2}$ ]

Discussion

16.	Light of the wavelength 550 nm falls normally on a slit of width 22.0×10−5cm. The angular position of the second minima from the central maxima will be :
Answer» Light of the wavelength $550 nm$ falls normally on a slit of width $22.0 \times 10^{- 5} cm$ . The angular position of the second minima from the central maxima will be :

Discussion

17.	An object of mass 1 kg attached to the string of length 1 m is whirled in a vertical circle at a constant angular speed. If the maximum tension in the string is 60 N, then what is the speed of the object at the lowest point?
Answer» An object of mass $1 kg$ attached to the string of length $1 m$ is whirled in a vertical circle at a constant angular speed. If the maximum tension in the string is $60 N$ , then what is the speed of the object at the lowest point?

Discussion

18.	Determine the amount of 21084Po (in micrograms) necessary to provide a source of alpha particles of 5 millicurie strength. The half life of polonium is 138 days.
Answer» Determine the amount of $\begin{matrix} 21084 \end{matrix} P o$ (in micrograms) necessary to provide a source of alpha particles of $5$ millicurie strength. The half life of polonium is 138 days.

Discussion

19.	A solid sphere of mass 2 kg and diameter 10 cm is rolling without slipping at a speed of 5 ms−1. The rotational kinetic energy of the sphere will be
Answer» A solid sphere of mass $2 kg$ and diameter $10 cm$ is rolling without slipping at a speed of $5 {ms}^{- 1} .$ The rotational kinetic energy of the sphere will be

Discussion

20.	83.Assume that the potential energy of a hydrogen atom in its ground state is zero. Then its energy in the first excited state will be 1) 13.6eV 2) 27.2eV 3) 23.8eV 4) 10.2eV
Answer» 83.Assume that the potential energy of a hydrogen atom in its ground state is zero. Then its energy in the first excited state will be 1) 13.6eV 2) 27.2eV 3) 23.8eV 4) 10.2eV

Discussion

21.	P−V diagram of a diatomic gas is a straight line passing through origin. What is the molar heat capacity of the gas during the process?
Answer» $P - V$ diagram of a diatomic gas is a straight line passing through origin. What is the molar heat capacity of the gas during the process?

Discussion

22.	The electric field in a region is radially outward with magnitude E=r2+2. The charge contained in a sphere of radius a = 2 m centred at the origin is 16πε0x. Find the value of x. ___
Answer» The electric field in a region is radially outward with magnitude $E = r^{2} + 2$ . The charge contained in a sphere of radius a = 2 m centred at the origin is $16 π ε_{0} x$ . Find the value of x. ___

Discussion

23.	A beam of hydrogen molecules is directed toward a wall, at an angle 32∘ with the normal to the wall. Each molecule in the beam has a speed of 1.0 km/s and a mass of 3.3×1024g. The beam strikes the wall over an area of 2.0 Cm2, at a rate of 4.0×1023 molecules per second. What is the beam's pressure on the wall?
Answer» A beam of hydrogen molecules is directed toward a wall, at an angle $32^{\circ}$ with the normal to the wall. Each molecule in the beam has a speed of 1.0 km/s and a mass of $3.3 \times 10^{24} g$ . The beam strikes the wall over an area of $2.0 C m^{2}$ , at a rate of $4.0 \times 10^{23}$ molecules per second. What is the beam's pressure on the wall?

Discussion

24.	Rain is falling vertically with a speed of 35m/s. A woman rides a bicycle with a speed of12m/s in East to West suite direction. What is the director in which she should hold her umbrella?
Answer» Rain is falling vertically with a speed of 35m/s. A woman rides a bicycle with a speed of12m/s in East to West suite direction. What is the director in which she should hold her umbrella?

Discussion

25.	26. If a body loss his half velocity of 6cm penetrating a wooden block so how much it will penetrate more before coming to rest
Answer» 26. If a body loss his half velocity of 6cm penetrating a wooden block so how much it will penetrate more before coming to rest

Discussion

26.	Why gun recoils when bullet is been fired? Is it because of conservation of momentum or this happens that's why it called conservation of momentum?
Answer» Why gun recoils when bullet is been fired? Is it because of conservation of momentum or this happens that's why it called conservation of momentum?

Discussion

27.	When a potential difference of 103 V is applied between A and B, a charge of 0.75 mC is stored in the system of capacitors. The value of C is (in μF)
Answer» When a potential difference of $10^{3} V$ is applied between $A$ and $B$ , a charge of $0.75 mC$ is stored in the system of capacitors. The value of $C$ is (in $μ F$ )

Discussion

28.	106. From the velocity time graph of a particle moving in a straight line. The ratio of average velocity for interval 3s and instantaneous velocity at 3s.
Answer» 106. From the velocity time graph of a particle moving in a straight line. The ratio of average velocity for interval 3s and instantaneous velocity at 3s.

Discussion

29.	A stone is thrown vertically upward with a speed of 28 m/s. (a) Find the maximum height reached by the stone. (b) Find its velocity one second before it reaches the maximum height. (c) Does the answer of part (d) Change if the initial speed is more than 28 m/s such as 40 m/s or 80 m/s ?
Answer» A stone is thrown vertically upward with a speed of 28 m/s. (a) Find the maximum height reached by the stone. (b) Find its velocity one second before it reaches the maximum height. (c) Does the answer of part (d) Change if the initial speed is more than 28 m/s such as 40 m/s or 80 m/s ?

29.

A stone is thrown vertically upward with a speed of 28 m/s. (a) Find the maximum height reached by the stone. (b) Find its velocity one second before it reaches the maximum height. (c) Does the answer of part (d) Change if the initial speed is more than 28 m/s such as 40 m/s or 80 m/s ?

Answer»

A stone is thrown vertically upward with a speed of 28 m/s.

(a) Find the maximum height reached by the stone.

(b) Find its velocity one second before it reaches the maximum height.

(c) Does the answer of part

(d) Change if the initial speed is more than 28 m/s such as 40 m/s or 80 m/s ?

Discussion

30.	Find the position of the centre of mass of T - shaped lamina of negligible thickness as shown in figure. Assume the origin to be at the intersection of axes and take the mass density of the lamina, σ=1 kg/m2
Answer» Find the position of the centre of mass of $T$ - shaped lamina of negligible thickness as shown in figure. Assume the origin to be at the intersection of axes and take the mass density of the lamina, $σ = 1 {kg/m}^{2}$

Discussion

31.	Is the force between the plates of a PPC given by F=(sigma)^2/2(EPSILON KNOT) or by F=(sigma)^2/2K(EPSILON KNOT) ?
Answer» Is the force between the plates of a PPC given by F=(sigma)^2/2(EPSILON KNOT) or by F=(sigma)^2/2K(EPSILON KNOT) ?

Discussion

32.	One end of a cylindrical glass rod ends in a hemispherical surface of radius R = 20 mm.- Find the image distance of a point object on the axis of the rod, 80 mm to the left of the vertex. The rod is in air.
Answer» One end of a cylindrical glass rod ends in a hemispherical surface of radius R = 20 mm. - Find the image distance of a point object on the axis of the rod, 80 mm to the left of the vertex. The rod is in air.

Discussion

33.	What is the momentum of photon of energy 3 MeV in kgms−1?
Answer» What is the momentum of photon of energy 3 MeV in $k g m s^{- 1}$ ?

Discussion

34.	A charged drop of oil of radius 2.76 micrometer and density 920 kg/m^3 is held stationary in a vertically downward electric field of 1.65 x 10^6 N/C.(i) Find the magnitude and sign of the charge on the drop.(ii) If the drop captures two electrons in the same electric field , what would be its acceleration ? Ignore viscous drag.
Answer» A charged drop of oil of radius 2.76 micrometer and density 920 kg/m^3 is held stationary in a vertically downward electric field of 1.65 x 10^6 N/C. (i) Find the magnitude and sign of the charge on the drop. (ii) If the drop captures two electrons in the same electric field , what would be its acceleration ? Ignore viscous drag.

Discussion

35.	A point charge produces an electric field of magnitude 5.0NC−1 at a distance of 40 cm from it. What is the magnitude of the charge?
Answer» A point charge produces an electric field of magnitude $5.0 N C^{- 1}$ at a distance of 40 cm from it. What is the magnitude of the charge?

Discussion

36.	A stone tied to a string is rotated in a circle. If the string is cut, the stone flies away from the circle because
Answer» A stone tied to a string is rotated in a circle. If the string is cut, the stone flies away from the circle because

Discussion

37.	Will wavelength and frequency both change for refracted ray to keep the speed a constant?
Answer» Will wavelength and frequency both change for refracted ray to keep the speed a constant?

Discussion

38.	A long straight wire along the z - axis carries a current i in the negative z - direction. The magnetic field →B at a point having co - ordinate (x, y) on the z = 0 plane is
Answer» A long straight wire along the z - axis carries a current i in the negative z - direction. The magnetic field $\to B$ at a point having co - ordinate (x, y) on the z = 0 plane is

Discussion

39.	Explain about the launching of satellite in a particular orbit.
Answer» Explain about the launching of satellite in a particular orbit.

Discussion

40.	Question 24Explain how lightning takes place.
Answer» Question 24 Explain how lightning takes place.

40.

Question 24Explain how lightning takes place.

Answer»

Question 24

Explain how lightning takes place.

Discussion

41.	A plane electromagnetic wave of frequency 25 GHz is propagating in vacuum along the z−direction. At a particular point in space and time, the magnetic field is given by →B=5×10−8^j T. The corresponding electric field →E is (speed of light c=3×108 ms−1)
Answer» A plane electromagnetic wave of frequency $25 GHz$ is propagating in vacuum along the $z -$ direction. At a particular point in space and time, the magnetic field is given by $\to B = 5 \times 10^{- 8}^j T .$ The corresponding electric field $\to E$ is $(speed of light c = 3 \times 10^{8} {ms}^{- 1})$

Discussion

42.	If ∫cos(lnx)x3dx=1ax2[bsin(lnx)−ccos(lnx)]+K, where K is the constant of integration, then the value of a+b+c is
Answer» If $\int \frac{cos (ln x)}{x^{3}} d x = \frac{1}{a x^{2}} [b sin (ln x) - c cos (ln x)] + K,$ where $K$ is the constant of integration, then the value of $a + b + c$ is

Discussion

43.	For the system shown in the figure, the cylinder on left has a mass (M) of 25 kg and cross-sectional area 20cm2 and is connected to a spring of spring constant 1400 N/m. The piston on the right has mass m =5kg and cross-sectional area 4 cm2 . The minimum mass m, to be kept on m so that water spills out from the left is(initially water level in both limbs is same) [The height of cylinder in left limb is 5 cm]
Answer» For the system shown in the figure, the cylinder on left has a mass (M) of 25 kg and cross-sectional area 20cm² and is connected to a spring of spring constant 1400 N/m. The piston on the right has mass m =5kg and cross-sectional area 4 cm² . The minimum mass m^, to be kept on m so that water spills out from the left is(initially water level in both limbs is same) [The height of cylinder in left limb is 5 cm]

43.

For the system shown in the figure, the cylinder on left has a mass (M) of 25 kg and cross-sectional area 20cm2 and is connected to a spring of spring constant 1400 N/m. The piston on the right has mass m =5kg and cross-sectional area 4 cm2 . The minimum mass m, to be kept on m so that water spills out from the left is(initially water level in both limbs is same) [The height of cylinder in left limb is 5 cm]

Answer»

For the system shown in the figure, the cylinder on left has a mass (M) of 25 kg and cross-sectional area 20cm² and is connected to a spring of spring constant 1400 N/m. The piston on the right has mass m =5kg and cross-sectional area 4 cm² . The minimum mass m^, to be kept on m so that water spills out from the left is(initially water level in both limbs is same) [The height of cylinder in left limb is 5 cm]

Discussion

44.	A solid body rotates about a statinary axis so that its angular velocity depends on the rotalional angle φ as w=wo-ko, where wo & k are positive constants. At the moment t=0, the angle φ=0. Find the time dependence of rotation angle.
Answer» A solid body rotates about a statinary axis so that its angular velocity depends on the rotalional angle φ as w=wo-ko, where wo & k are positive constants. At the moment t=0, the angle φ=0. Find the time dependence of rotation angle.

Discussion

45.	A string is stretched along the x-axis. There is a transverse disturbance along the string given by the equation ϕ(x,t)=4sin(πx3)cos(10πt)where x is measured in centimeters and t in second. Both waves moving towards each other create this disturbance. Assume the velocities and amplitudes are equal for the two waves.
Answer» A string is stretched along the x-axis. There is a transverse disturbance along the string given by the equation $ϕ (x, t) = 4 s i n (\frac{π x}{3}) c o s (10 π t)$ where x is measured in centimeters and t in second. Both waves moving towards each other create this disturbance. Assume the velocities and amplitudes are equal for the two waves.

Discussion

46.	A binary star consists of two stars A (mass 2.2M_s) and B (mass 11M_s), where M_s is the mass of the sun. They are seperated by dis†an ce d and are rotating about their centre of mass , which is stationary . The ratio of the total angular momentum of the binary star to the angular momentum of star B about the centre of mass is
Answer» A binary star consists of two stars A (mass 2.2M_s) and B (mass 11M_s), where M_s is the mass of the sun. They are seperated by dis†an ce d and are rotating about their centre of mass , which is stationary . The ratio of the total angular momentum of the binary star to the angular momentum of star B about the centre of mass is

Discussion

47.	10.: A launch takes 3 hrs to go downstream from point A to B and 6hrs to come back to A from B. The time taken by the launch to cover the same distance downstream when its engine cutoff is?
Answer» 10.: A launch takes 3 hrs to go downstream from point A to B and 6hrs to come back to A from B. The time taken by the launch to cover the same distance downstream when its engine cutoff is?

Discussion

48.	Classify the following measures as scalars and vectors. (i) 10 kg (ii) 2 metres north-west (iii) 40° (iv) 40 watt (v) 10–19 coulomb (vi) 20 m/s2
Answer» Classify the following measures as scalars and vectors. (i) 10 kg (ii) 2 metres north-west (iii) 40° (iv) 40 watt (v) 10^–19 coulomb (vi) 20 m/s²

48.

Classify the following measures as scalars and vectors. (i) 10 kg (ii) 2 metres north-west (iii) 40° (iv) 40 watt (v) 10–19 coulomb (vi) 20 m/s2

Answer»

Classify
the following measures as scalars and vectors.

(i) 10
kg (ii) 2 metres north-west (iii) 40°

(iv) 40
watt (v) 10^–19 coulomb (vi) 20 m/s²

Discussion

49.	Question 26 (a)(a) A cube of side 5 cm is immersed in water and then in saturated salt solution. In which case will it experience a greater buoyant force. If each side of the cube is reduced to 4 cm and then immersed in water, what will be the effect on the buoyant force experienced by the cube as compared to the first case for water. Give reason for each case.
Answer» Question 26 (a) (a) A cube of side 5 cm is immersed in water and then in saturated salt solution. In which case will it experience a greater buoyant force. If each side of the cube is reduced to 4 cm and then immersed in water, what will be the effect on the buoyant force experienced by the cube as compared to the first case for water. Give reason for each case.

Discussion

50.	For a particle undergoing rectilinear motion with uniform acceleration, the magnitude of displacement is one third the dis†an ce covered in some time interval. The magnitude of final velocity is less than magnitude of initial velocity for this time interval. Then the ratio of initial speed to the final speed for this time interval is : (A) V2 (B) 2 (C) 73 (D) 3
Answer» For a particle undergoing rectilinear motion with uniform acceleration, the magnitude of displacement is one third the dis†an ce covered in some time interval. The magnitude of final velocity is less than magnitude of initial velocity for this time interval. Then the ratio of initial speed to the final speed for this time interval is : (A) V2 (B) 2 (C) 73 (D) 3

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

The anode voltage of a photocell is kept fixed. The wavelength λ of the light falling on the cathode is gradually changed. The plate current I of the photocell varies with λ as follows :

A vertical wire kept in xz-plane carries a current from Q to P as shown in figure. The magnetic field due to current will have the direction at the origin O along

A gas is suddenly compressed to 1/4th of its original volume.what will be the rise in temperature if it's initial temperature is27°C(given adiabatic constant=1.5)

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Consider the discrete time signalx(n)=(13)nu(n),whereu(n)={1,n≥00,n&lt;0and y(n)=x(−n), −∞&lt;n&lt;∞Then ∞∑n=−∞y(n) is______.1.5

Two plane mirrors M1 and M2 each have length 1 m and are separated by 1 cm. A ray of light is incident on one end of mirror M1 at an angle of 45∘. How many reflections will the ray have before going out from the other end?

what is meant by an impact time and how to calculate it ?

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A trolley of mass 300 kg carrying a sandbag of 25 kg is moving uniformly with a speed of 27 km/h on a frictionless track. After a while, sand starts leaking out of a hole on the floor of the trolley at the rate of 0.05 kg s¯¹. What is the speed of the trolley after the entire sand bag is empty ?

A ball of mass m=2 kg is travelling under the influence of gravity. At height H=5 m speed of ball is u=10 m/s as shown in figure. Find the torque due to gravity about x axis.

The work done in increasing the length of a 1 m long wire of cross-sectional area 1 mm2 through 1 mm will be [Given, Y=2×1011 N/m2]

Light of the wavelength 550 nm falls normally on a slit of width 22.0×10−5cm. The angular position of the second minima from the central maxima will be :

An object of mass 1 kg attached to the string of length 1 m is whirled in a vertical circle at a constant angular speed. If the maximum tension in the string is 60 N, then what is the speed of the object at the lowest point?

Determine the amount of 21084Po (in micrograms) necessary to provide a source of alpha particles of 5 millicurie strength. The half life of polonium is 138 days.

A solid sphere of mass 2 kg and diameter 10 cm is rolling without slipping at a speed of 5 ms−1. The rotational kinetic energy of the sphere will be

83.Assume that the potential energy of a hydrogen atom in its ground state is zero. Then its energy in the first excited state will be 1) 13.6eV 2) 27.2eV 3) 23.8eV 4) 10.2eV

P−V diagram of a diatomic gas is a straight line passing through origin. What is the molar heat capacity of the gas during the process?

The electric field in a region is radially outward with magnitude E=r2+2. The charge contained in a sphere of radius a = 2 m centred at the origin is 16πε0x. Find the value of x. ___

Rain is falling vertically with a speed of 35m/s. A woman rides a bicycle with a speed of12m/s in East to West suite direction. What is the director in which she should hold her umbrella?

26. If a body loss his half velocity of 6cm penetrating a wooden block so how much it will penetrate more before coming to rest

Why gun recoils when bullet is been fired? Is it because of conservation of momentum or this happens that's why it called conservation of momentum?

When a potential difference of 103 V is applied between A and B, a charge of 0.75 mC is stored in the system of capacitors. The value of C is (in μF)

106. From the velocity time graph of a particle moving in a straight line. The ratio of average velocity for interval 3s and instantaneous velocity at 3s.

A stone is thrown vertically upward with a speed of 28 m/s. (a) Find the maximum height reached by the stone. (b) Find its velocity one second before it reaches the maximum height. (c) Does the answer of part (d) Change if the initial speed is more than 28 m/s such as 40 m/s or 80 m/s ?

Find the position of the centre of mass of T - shaped lamina of negligible thickness as shown in figure. Assume the origin to be at the intersection of axes and take the mass density of the lamina, σ=1 kg/m2

Is the force between the plates of a PPC given by F=(sigma)^2/2(EPSILON KNOT) or by F=(sigma)^2/2*K*(EPSILON KNOT) ?

One end of a cylindrical glass rod ends in a hemispherical surface of radius R = 20 mm.- Find the image distance of a point object on the axis of the rod, 80 mm to the left of the vertex. The rod is in air.

What is the momentum of photon of energy 3 MeV in kgms−1?

A point charge produces an electric field of magnitude 5.0NC−1 at a distance of 40 cm from it. What is the magnitude of the charge?

A stone tied to a string is rotated in a circle. If the string is cut, the stone flies away from the circle because

Will wavelength and frequency both change for refracted ray to keep the speed a constant?

A long straight wire along the z - axis carries a current i in the negative z - direction. The magnetic field →B at a point having co - ordinate (x, y) on the z = 0 plane is

Explain about the launching of satellite in a particular orbit.

Question 24Explain how lightning takes place.

A plane electromagnetic wave of frequency 25 GHz is propagating in vacuum along the z−direction. At a particular point in space and time, the magnetic field is given by →B=5×10−8^j T. The corresponding electric field →E is (speed of light c=3×108 ms−1)

If ∫cos(lnx)x3dx=1ax2[bsin(lnx)−ccos(lnx)]+K, where K is the constant of integration, then the value of a+b+c is

A solid body rotates about a statinary axis so that its angular velocity depends on the rotalional angle φ as w=wo-ko, where wo & k are positive constants. At the moment t=0, the angle φ=0. Find the time dependence of rotation angle.

10.: A launch takes 3 hrs to go downstream from point A to B and 6hrs to come back to A from B. The time taken by the launch to cover the same distance downstream when its engine cutoff is?

Classify the following measures as scalars and vectors. (i) 10 kg (ii) 2 metres north-west (iii) 40° (iv) 40 watt (v) 10–19 coulomb (vi) 20 m/s2

Consider the discrete time signalx(n)=(13)nu(n),whereu(n)={1,n≥00,n<0and y(n)=x(−n), −∞<n<∞Then ∞∑n=−∞y(n) is______.1.5

Is the force between the plates of a PPC given by F=(sigma)^2/2(EPSILON KNOT) or by F=(sigma)^2/2K(EPSILON KNOT) ?