Question 2 :
In a current-carrying solenoid, the magnetic field direction is given by the right hand rule such that the
Question 3 :
A wire of length $$L$$ is made in the form of a coil in a moving coil galvanometer. To have maximum sensitiveness the shape of the coil is <br/>
Question 4 :
A solenoid of $$2.5\ m$$ length and $$2.0\ cm$$ diameter possesses $$10$$ turns per cm. A current of $$0.5\ A$$ is flowing through it. The magnetic induction at axis inside the solenoid is
Question 6 :
The magnetic field lines inside the solenoid are in the form of
Question 7 :
In cyclotron, for a given magnet, radius of the semicircle traced by positive ion is directly proportional to ($$v=$$ velocity of positive ion).<br/>
Question 9 :
In which  form  the field lines inside the infinite solenoid are present ?<br/>
Question 10 :
In cyclotron, radius of circular path traced by positive ions is ____________.
Question 11 :
The radial magnetic field is used in a suspendedcoil galvanometer to provide<br>
Question 12 :
A solenoid has length 0.4 cm, radius 1 cm and 400 turns of wire. If a current of 5 A is passed through this solenoid, what is the magnetic field inside the solenoid?
Question 13 :
A long solenoid has magnetic field strength of $$3.14\times 10^{-2}\ T$$ inside it when a current of $$5\ A$$  passes through it. The number of turns in $$1\ m$$ length of the solenoid is<br/>
Question 15 :
In a moving coil galvanometer, the deflection of the coil $$\theta$$ is related to the electric current $$i$$ by the relation<br>
Question 16 :
We have a galvanometer of resistance 25$$\Omega$$. It is shunted by a 2.5$$\Omega$$ wire, the part of total current that flows through the galvanometer is given as:
Question 17 :
The number of turns per unit length in a toroid is $$10^3$$and current flowing in it is $$\dfrac{1}{4\pi} A$$, then the magnetic induction produced in it, is :
Question 18 :
The strength of the magnetic field of solenoid increases with the decrease in number of turns in the solenoid.<br><br>
Question 19 :
Which of the following expressions are applicable to the moving coil galvanometer?
Question 20 :
The gyro-magnetic ratio of an electron in an H-atom, according to Bohr's model, is
Question 21 :
Two thin long parallel wires separated by a distance $$b$$ are carrying a current $$I$$ ampere each. The magnitude of the force per unit length exerted by one wire on the other is<br>
Question 22 :
A deuteron of kinetic energy $$50\ keV$$ is describing a circular orbit of radius $$0.5$$ metre in a plane perpendicular to the magnetic field $$B$$. The kinetic energy of the proton that describes a circular orbit of radius $$0.5$$ metre in the same plane with the same $$B$$ is
Question 23 :
If a proton, deutron and $$\alpha-$$particle or being accelerated by the same potential difference entersperpendicular to the magnetic field, then the ratio of their kinetic energy is<br>
Question 24 :
A coil of one turn is made of a wire of certain length and then from the same length a coil of two turns is made. Ifthe same current is passed in both the cases, then the ratio of the magnetic induction at their centres will be :
Question 25 :
An electron of energy 1800 eV describes a circular path in magnetic field of flux density 0.4 T. The radius of path is (q = 1.6 X $$10^{-19}$$ C, $$m_e$$ = 9.1 X $$10^{-31}$$ kg)
Question 26 :
The radius of curvature of the path of the charges particles in a uniform magnetic field is directly proportional to
Question 29 :
Two circular coils of wires made of wire of same gauge have the same number of turns and have radii 20 cm and 40 cm. They are connected in parallel to a battery. The ratio of the magnetic inductions at the centers of the coils is:<br/>
Question 30 :
The force of repulsion between two parallel wires is $$f$$ when each one of them carries a certain current $$I$$. If the current in each is doubled, the force between them would be 
Question 31 :
Two conductors each of length $$12m$$ lie parallel to each other in air. The centre to centre distance between the two conductors is $$15\times 10^{-2}m$$ and the current in each conductor is $$300A$$. The force in newton tending to pull the conductors together is:<br/>
Question 32 :
The force between two parallel wires carrying currents has been used to define
Question 33 :
To obtain maximum intensity of magnetic field at a point the angle between position vector of point and small elements of length of the conductor is<br>
Question 34 :
An electron is projected with a velocity $$3\times 10^{10}ms^{-1}$$ at right angle to a uniform magnetic field of induction $$0.2 T$$. The radius of the orbit that the electron revolves is <br/>(Charge of $$e=1.6\times 10^{-19}C$$, $$m_{e}=9.1\times 10^{-31}kg$$ )<br/>
Question 35 :
Assertion: The magnetic filed at the ends of a very long current carrying solenoid is half of that at the center.
Reason: If the solenoid is sufficiently long, the field within it is uniform.
Question 36 :
A charged particle enters a magnetic field H with its initial velocity making an angle of $$45^o$$ with H. Then the path of the particle will be<br>
Question 37 :
Two long conductors, separated by a distance d carry currents $$ I_{1}$$ and  $$ I_{2}$$ in the same direction. They exert a force F on each other. Now the current in one of them is increased to two times and its direction is reversed. The distance is also increased to 3 times. The new value of the force between them is :<br/>
Question 38 :
A small current carrying loop of area $$A$$ behaves like a tiny magnet of magnetic moment $$M$$. Current in the loop is
Question 39 :
When radiation emitted by a radioactive substance is subjected to a magnetic field, alpha-particles describe a circle in the clockwise direction
Question 40 :
A proton is moving in a magnetic field. The field $$\overrightarrow {B} $$ is into the plane of the page. The velocity vector $$\overrightarrow{V}$$ lies in the plane of the page, perpendicular to $$\overrightarrow {B} $$. The motion of proton. 
Question 41 :
A charged particle moves in a gravity free space where an electric field of strength E and a magnetic field of induction B exist. Which of the following statement is/are correct?<br>
Question 42 :
In which case will the particle move in a straight line with constant velocity?
Question 43 :
An electron $$($$mass $$=9.1\times 10^{-31}$$; charge $$=-1.6\times 10^{-19}\mathrm{C})$$ experiences no deflection if subjected to an electric field of $$3.2\times 10^{5}\mathrm{V}/\mathrm{m}$$ and a magnetic field of $$2.0\times 10^{-3}\mathrm{W}\mathrm{b}/\mathrm{m}^{2}$$. Both the fields are normal to the path of electron and to each other. Ifthe electric field is removed, then the electron will revolve in an orbit of radius :<br>
Question 44 :
An electron beam passes through a magnetic field of $$2\times 10^{-3}Wb/m^2$$ and an electric field of $$1.0\times 10^4 V/m$$ both acting simultaneously. The path of electron remains undeviating. The speed of electron if the electric field is removed, and the radius of electron path will be respectively.<br>
Question 45 :
A current of i ampere is flowing in an equilateral triangle of side a. The magnetic induction at the centroid will be?
Question 46 :
A and B are two like parallel forces. A couple of moment H lies in the plane of A and B and is contained with them. The resultant of A and B after combining is displaced through a distance 
Question 47 :
A photon of energy E ejects a photoelectron from a metal surface whose work function is $$W_0.$$ If this electron enters into a uniform magnetic field of induction B in a direction perpendicular to the field and describes a circular path of radius r, then the radius r is given by (in the usual notation)
Question 48 :
A charged particle is moving along positive y-axis in uniform electric and magnetic fields<br/>             $$\vec{E}={E}_{o}\hat{k}$$   and   $$\vec{B}={B}_{o}\hat{i}$$Here $${E}_{o}$$ and $${B}_{o}$$ are positive constants.Choose the correct options.
Question 49 :
A coil of resistance $$40\Omega$$ is connected to a galvanometer of $$160\Omega$$ resistance. The coil has radius $$6$$mm and turns $$100$$. This coil is placed between the poles of a magnet such that magnetic field is perpendicular to coil. If coil is dragged out then the charge through the galvanometer is $$32\mu C$$. The magnetic field is?
Question 50 :
A long solenoid of radius $$2$$ cm has $$100$$ turns/cm and carries a current of $$5A$$. A coil of radius $$1$$ cm having $$100$$ turns and a total resistance of $$20\Omega$$ placed inside the solenoid co-axially. The coil is connected to galvanometer. If current in the solenoid is reversed in direction. Fine the charge flow through the galvanometer.
Question 51 :
A particle of charge $$q$$ and mass $$m$$ starts moving from the origin under the action of an electric field $$\overrightarrow{E}=E_o\hat{i}$$ and $$\overrightarrow{B}=B_0\hat{i}$$ with a velocity $$\overrightarrow{v}=v_0\hat{j}$$. The speed of the particle will become $$2v_0$$ after a time<br>
Question 52 :
A charged particle moves with a constant velocity $$(\hat{i}+\hat{j})$$m/s in a magnetic field $$\vec{B}=(2\hat{i}+3\hat{k})$$and uniformelectric field $$\vec{E}=(a\hat{i}+b\hat{j}+c\hat{k})$$N/C, then $$($$assuming all quantities in S.I. unit$$) :$$
Question 53 :
A charged particle revolves in circular path in uniform magnetic field after accelerating by a potential difference of V volts.Choose the correct options if V is doubled.
Question 54 :
In a mass spectrometer used for measuring the masses of ions, the ions are initially accelerated by an electric potential $$V$$ and then made to follow semicircular paths of radius $$R$$ using a magnetic field $$B.$$ If $$V$$ and $$B$$ are kept constant, the ratio $$\left(\dfrac{charge \  on \  the \  ion}{mass \  of \  the \  ion}\right)$$ will be proportional to
Question 55 :
When a proton is released from rest in room, it starts with an initial acceleration $${ a }_{ 0 }$$ towards west When it is projected towards north with a speed $${ V }_{ 0 }$$ it moves with an initial acceleration $${ 3a }_{ 0 }$$ towards west. The electric and magnetic fields in the room are :
Question 56 :
A cyclotron is operated at an oscillator frequency of $$\dfrac{80}{\pi }MHz$$ and has a Dee of radius $$\:R = 60\ cm$$. The magnitude of magnetic field $$B$$ (in Tesla) to accelerate deuteron is $$\dfrac{x}{10}$$ Tesla. Find x ? (charge on deuteron $$e=1.6\times10^{-19}$$ mass of deuteron $$=3.24\times 10^{-27}\ Kg)$$<br/>
Question 57 :
(A) In tangent galvanometer the circular frame is rotated until the plane of the coil is parallel to magnetic meridian<br>(B) In tangent galvanometer current through it is related to deflection of needle as
Question 59 :
A proton and a deuteron ion having the same kinetic energies enter a region of uniform magnetic field perpendicularly. Deuteron's mass is twice that of proton. Calculate the ratio of the radii of their circular paths.
Question 60 :
The field normal to the plane of wire of $$n$$ turns and radius $$r$$ which carries a current $$i$$ is measured on the axis at a small distance $$h$$ from the centre of the coil. This is smaller than the field at the centre by the fraction
