Email

Chat with tutors

Login

Ask Questions, Get Answers

Menu X

home ask tuition questions practice papers mobile tutors pricing

X

Recent questions in Physics

Questions >> JEEMAIN and NEET >> Physics

Physics

A rigid circular loop of radius $ r$ lies in the $x-y$ plane on a flat table and a current $i$ flows through it. At this place, the earth’s magnetic field is $B_x\hat i + B_z \hat k$ . The value of $i$ so that one end of the loop lifts up from the table is

asked Feb 23, 2014 by thanvigandhi_1

1 answer

A conducting rod of mass $m$ and length $L$ is moving down a smooth incline plane on inclination $ \theta$ with constant velocity $ v$. A current $i$ is flowing in the conductor in a direction perpendicular to the paper inwards. A vertically upward magnetic field $ \overrightarrow B$ exists in space. Its magnitude is

asked Feb 23, 2014 by thanvigandhi_1

1 answer

Where $\;0.5 A^{0}\;$ x-rays strike a material , the photoelectrons from K shell are observed to move in a circle of radius 23mm in a magnetic fields of $\;2\times10^{-2}T\;.$ Than the binding energy of K-shell electrons is

asked Feb 23, 2014 by yamini.v

1 answer

The dimensions of $ \large\frac{B^2C^2R^2}{2\mu_0}$ where $B$ is magnetic field,$ R$ is resistance and $ C$ is capacitance are

asked Feb 23, 2014 by thanvigandhi_1

1 answer

Magnetic field at the centre of a circular loop of area $A$ is $B$. Then magnetic moment of the loop is

asked Feb 23, 2014 by thanvigandhi_1

1 answer

A proton, a deuteron and an $ \alpha$ - particle having the same kinetic energy are moving in circular trajectories in a constant magnetic field. If $r_p, r_d$ and $r_{\alpha}$ denote respectively the radii of the trajectories of these particles, then

asked Feb 23, 2014 by thanvigandhi_1

1 answer

A battery is connected between two points $A$ and $B$ on the circumference of a uniform conducting ring of radius $r$ and resistance $R$. One of the arcs $AB$ of the ring subtends an angle $ \theta$ at the centre. The intensity of the magnetic field at the centre due to a constant current in the ring is

asked Feb 23, 2014 by thanvigandhi_1

1 answer

If the $\;K_{\alpha}\;$ radiation of $\;M_{0}\;(Z=42)\;$ has a wavelength of $\;0.71 A^{0}\;$ , than the wavelength of corresponding radiation of Cu , i. e , $\;K_{\alpha}$ for Cu $\;(z=29)\;$ assuming $\;\sigma=1\;$ .

asked Feb 22, 2014 by yamini.v

1 answer

A perfectly reflecting solid sphere of radius r is kept in the path of a parallel beam of light of large aperture . If the beam carries an intensity I find force exerted by beam on sphere .

asked Feb 22, 2014 by yamini.v

1 answer

A plate of mass 10gm is in equilibrium in air due to force exerted by light beam on plate . Assuming plate is perfectly absorbing the power of beam is :

asked Feb 22, 2014 by yamini.v

1 answer

Light described at a place by the equation $\;\varepsilon=(100 V/m)\;[sin(5\times10^{15} s^{-1})t+sin(8 \times10^{15})t]\;$ falls on a metal surface having work function 2eV . Than maximum kinetic energy of photo electrons will be :

asked Feb 22, 2014 by yamini.v

1 answer

A photocell is operating in saturation mode with a aphotocurrent 4.8mA when a monochromatic radiation of wavelength $\;3000A^{0}\;$ and power 1mW is incident. When another monochromatic radiation of wavelength $\;1650A^{0}\;$ and power 5mW is incident , it is observed that maximum velocity of photoelectron generation per incident to be same for both cases . Than the threshold wavelength for cell is : Find saturation current in second case

asked Feb 22, 2014 by yamini.v

1 answer

A circular loop of radius $R$, carrying a current $i$ lies in the $x-y$ plane with its centre at the origin. The total magnetic flux through the $x-y$ plane is

asked Feb 22, 2014 by thanvigandhi_1

1 answer

The magnetic field at the centre of an equilateral triangular loop of side $2L$ carrying a current $i$ is

asked Feb 22, 2014 by thanvigandhi_1

1 answer

Same current is flowing in three infinitely long wires along positive $x, y$ and $z$ directions. The magnetic field at the point $(0, 0, -a)$ would be

asked Feb 22, 2014 by thanvigandhi_1

1 answer

A wire of length $\ell$ is bent to form a circular coil of some turns. A current $i$ flows through the coil and is placed in a uniform magnetic field $B$. The maximum torque on the coil can be

asked Feb 22, 2014 by thanvigandhi_1

1 answer

A conducting rod of mass $m$ and length $\ell$ is placed over a smooth table. A uniform magnetic field is acting perpendicular to the rod. Charge $q$ is suddenly passed through the rod and it acquires a velocity $v$ on the surface, then $q$ is equal to

asked Feb 22, 2014 by thanvigandhi_1

1 answer

A charged particle is projected with velocity $ \upsilon_0$ along the positive $x$ - axis. The magnetic field $B$ is directed along negative $z$ - axis for the region $0<x<L$. The particle emerges out at $x = L$ at an angle of $60^{\circ}$ with the direction of projection. Find the velocity with which the same particle is projected at $x=0$ along the $+ve\: x$ - axis so that when it emerges out at $x = L$, the angle made by it is $30^{\circ}$ direction of projection with the

asked Feb 22, 2014 by thanvigandhi_1

1 answer

A charge particle moves in a circular path in possible electric and magnetic fields. Which of the following scenarios is possible?

asked Feb 22, 2014 by thanvigandhi_1

1 answer

In a coaxial straight cable, the central conductor and the outer conductor carry equal currents in opposite directions. The magnetic field is zero

asked Feb 22, 2014 by thanvigandhi_1

1 answer

Two parallel wires carry currents $20A$ and $40A$ in the opposite directions. Another wire carrying a current $30A$ parallel to $40A$ is placed mid-way between the two wires. The force on it will be

asked Feb 22, 2014 by thanvigandhi_1

1 answer

An electric current $\imath$ enters and leaves a uniform circular wire of radius $ \Re$ through diametrically opposite points. A charged particle q moving along the axis of the circular wire passes through the centre at speed $v$. The magnetic force acting on the particle when it passes through the centre is

asked Feb 22, 2014 by thanvigandhi_1

1 answer

A ring of mass m, radius R having charge q uniformly distributed over it and free to rotate about its own axis is placed in a region having a magnetic field B parallel to its axis. If the magnetic field is suddenly switched off, the angular velocity acquired by the ring is

asked Feb 22, 2014 by thanvigandhi_1

1 answer

Circular arc of a wire of radius R makes an angle of 3π/2 radians at the centre. If a current i flows through it, the magnetic field intensity at the centre of the circle will be

asked Feb 22, 2014 by thanvigandhi_1

1 answer

Two parallel connecting wires placed at a distance d apart carry equal currents in the same direction then the intensity of the magnetic field at a point between them will be

asked Feb 22, 2014 by thanvigandhi_1

1 answer

The force experienced by a pole of strength $100\: A-m$ at a distance of $0.2 \: m$ from a short magnet of length $10\: cm$ and pole strength $100\: A-m$ on its axial line will be

asked Feb 22, 2014 by thanvigandhi_1

1 answer

A uniform magnetic field exists in a region which forms an equilateral triangle of side $a$. The field is perpendicular to the plane of the triangle. A charge $q$ enters the triangle with speed $v$ along the $ \perp$ bisector of one of the sides and comes out along the $\perp$ bisector of the other side. Intensity of the magnetic field is

asked Feb 22, 2014 by thanvigandhi_1

1 answer

Consider the following statements \[\] Statement 1: If a charged particle is released in a region of uniform electric and magnetic fields parallel to each other, it will move in a straight line \[\] Statement 2: The magnetic field exerts no force on the particle but electric field does

asked Feb 22, 2014 by thanvigandhi_1

1 answer

Consider the following statements \[\] Statement 1: A long straight conductor carrying a current lies along the axis of a current carrying ring. The conductor will not exert any force on the ring \[\] Statement 2: The magnetic field due to a straight conductor coincides with the ring

asked Feb 22, 2014 by thanvigandhi_1

1 answer

Consider the following statements \[\] Statement 1: A cyclotron cannot accelerate neutrons \[\] Statement 2: Neutrons are neutral

asked Feb 22, 2014 by thanvigandhi_1

1 answer

A photocell is operating in saturation mode with a aphotocurrent 4.8mA when a monochromatic radiation of wavelength $\;3000A^{0}\;$ and power 1mW is incident. When another monochromatic radiation of wavelength $\;1650A^{0}\;$ and power 5mW is incident , it is observed that maximum velocity of photoelectron generation per incident to be same for both cases . Than the threshold wavelength for cell is : The efficiency of photoelectron generation will be

asked Feb 22, 2014 by yamini.v

1 answer

A photocell is operating in saturation mode with a aphotocurrent 4.8mA when a monochromatic radiation of wavelength $\;3000A^{0}\;$ and power 1mW is incident. When another monochromatic radiation of wavelength $\;1650A^{0}\;$ and power 5mW is incident , it is observed that maximum velocity of photoelectron generation per incident to be same for both cases . Than the threshold wavelength for cell is :

asked Feb 22, 2014 by yamini.v

1 answer

A small potassium foil is placed (perpendicular to direction of incidence of light ) a distance r (=0.5 m) from a point light source whose output power $\;P_{0}\;$ is 1W . Assuming wave nature of light . how long would it take for foil to soak up enough energy (=1.8eV) from the beam to eject on electron ? (Assume that ejected photoelectron collected its energy from a circular area of foil whose radius equals radius of potassium atom ($\;1.3\times10^{-10}m$))

asked Feb 22, 2014 by yamini.v

1 answer

A beam of light consists of 4 wavelength $\;4000A^{0},4800A^{0},6000A^{0}\; and\;7000A^{0}\;,$ each of intensity $\;1.5\times10^{-3}Wm^{-2}\;.$The beam falls normally on an area $\;10^{-4} m^2\;$ of a clean metallic surface of work function 1.9eV . Assuming no loss of light energy the no.of photoelectrons liberated per second is

asked Feb 22, 2014 by yamini.v

1 answer

In an experiment on photo electric emission , following observations were made ; (1) Wavelength of incident light = $\;1.98\times10^{-7}m\;$ 2 Stopping potential = $\;2.5 volt\;$. Then kinetic energy of photoelectrons with maximum speed and Thus hold frequency are respectively

asked Feb 22, 2014 by yamini.v

1 answer

A small particle of mass m moves in such a way that the potential energy $\;u=ar^2\;$ where a is a constant and r is the distance of particle from origin. Assuming Bohr's model of quantization of angular momentum and circular orbits. Then the radium of $\;n^{th}\;$ allowed orbit is

asked Feb 22, 2014 by yamini.v

1 answer

In a transition to a state of excitation energy 10.19eV , a hydrogen atom emits a $\;4890 A^{0}\;$ photon . Then the binding energy of initial state is :

asked Feb 22, 2014 by yamini.v

1 answer

A single electron orbits around a stationary nucleus of charge +ze , where z is a constant and e is magnitude of electronic charge. It requires 47.2eV to exite the electron from $\;2^{nd}\;$ Bohr orbital to $\;3^{rd}\;$ Bohr orbital. find the atomic no.of element.The wavelength of radiation required remove electron from first Bohr's orbit to infinity is

asked Feb 22, 2014 by yamini.v

1 answer

A single electron orbits around a stationary nucleus of charge +ze , where z is a constant and e is magnitude of electronic charge. It requires 47.2eV to exite the electron from $\;2^{nd}\;$ Bohr orbital to $\;3^{rd}\;$ Bohr orbital. find the atomic no.of element.

asked Feb 22, 2014 by yamini.v

1 answer

Electrons of energies 12.09 eV can cause radiation to be emitted from hydrogen atom. calculate the principal quantum number of the orbit to which the electron in the hydrogen atom is raised and the wavelength of radiation emitted if it drops back to the ground state .

asked Feb 21, 2014 by yamini.v

1 answer

Consider the following statements \[\] Statement 1: Free electrons are in a state of motion in a conductor. Even then no magnetic force acts on them unless a current is passed through it \[\] Statement 2: The average velocity of free electrons is zero

asked Feb 21, 2014 by thanvigandhi_1

1 answer

Consider the following statements \[\] Statement 1: If the current in the solenoid is reversed in direction while keeping the magnitude constant, the energy stored in the solenoid decreases \[\] Statement 2: Magnetic field energy is proportional to the square of the current

asked Feb 21, 2014 by thanvigandhi_1

1 answer

An insulating rod of length $ \ell$ carries a charge $q$ uniformly distributed on it. The rod is pivoted at its centre and is rotated with a frequency $F$ about a fixed axis perpendicular to the rod and passing through the pivot. The magnetic moment of the rod system is

asked Feb 21, 2014 by thanvigandhi_1

1 answer

A bar magnet of magnetic moment $4 A-m^2$ is free to rotate about a vertical axis through its centre. The magnet is released from rest from east-west position. Kinetic energy of the magnet in the north- south position will be $(H = 25 \mu T)$

asked Feb 21, 2014 by thanvigandhi_1

1 answer

A current carrying wire is kept along a magnetic line of force. The force experienced by the wire due to the magnetic field is

asked Feb 21, 2014 by thanvigandhi_1

1 answer

An electron falling under gravity enters a region of uniform magnetic field pointing north to south. The particle will deflect towards

asked Feb 21, 2014 by thanvigandhi_1

1 answer

If a current carrying coil having a magnetic moment $ \overrightarrow M$ is placed in a magnetic field $ \overrightarrow B$ , then the torque acting on it will be

asked Feb 21, 2014 by thanvigandhi_1

1 answer

The energy of an electron in an excited hydrogen atom is $\;-3.4 e V \;.$ Calculate the angular momentum of electron according to Bor's theorey. Plan ck's constant h= $\;6.626\times10^{-34} J-s\;.$

asked Feb 21, 2014 by yamini.v

1 answer

A negatively and uniformly charged disk is rotating in a clockwise direction as viewed from above. The direction of magnetic field at a point A is

asked Feb 21, 2014 by thanvigandhi_1

1 answer

The orbital magnetic dipole moment of electron in hydrogen atom is

asked Feb 21, 2014 by yamini.v

1 answer

Page:

« prev
1
...
22
23
24
25
26
27
28
...
60
next »

Feedback Terms Facebook Twitter About Us

Your payment for is successful.

...