Moving Charges ...

The magnetic force acting on a charged particle of charge -2 $\mu C$ in a magnetic field of 2T acting in y-direction. when the particle velocity is 
$\left( {2\widehat i + 3\widehat j} \right) \times 10^6 ms^{ - 1}$

Two paths  (path 1 and 2) followed by charge particles in magnetic field is shown in the figure. All the charge particles enters the magnetic field at A with equal kinetic energy. Choose the incorrect statement 

A long parallel straight conductors carry $i_{1}$ and $i_{2}(i_{1} > i_{2})$. When the currents are in same direction, the magnetic field at a point midway between the wires is $20 \mu T$. If the direction of $i_{2}$ is reversed, the field becomes $50 \mu T.$ The ratio of the current $i_{1}/ i_{2}$ is:

The coil of a dynamo is rotating in a magnetic field. The developed induced emf changes and the number of magnetic lines of force also changes. Which of the following conditions is correct?

A particle is moving in a region having a uniform magnetic field and a parallel, uniform electric field. At some instant, the velocity of the particle is perpendicular to the field direction. The path of the particle will be

A long straight wire carrying a current of 1.0 A is placed horizontally  in a uniform magnetic field $B = 1.0 \times 10 ^{-5} T$ pointing vertically upwards (figure). The magnitude of the resultant magnetic field at the points P and Q, both situated at a distance of $2.0 cm$ from the wire in the same horizontal plane are respectively.

A beam of electrons moving along +y direction enters  in a region of uniform electric and magnetic fields. If the beam goes undeflected through this region then field (B) and (E) are directed respectively: 

Two semi infinite wires AO and OC coinciding at O carry equal current I as shown in figure. Angle AOC is $\alpha$. The magnitude of magnetic field at a point P on the bisector of these two wires at a distance r from point O is

Two particle of charges +Q and -Q are projected from the same point with a velocity v in a region of uniform magnetic field B such that the velocity vector makes $\theta$ with the magnetic field. Their masses are M and 2M respectively. Then, they will meet again for the first time at a point whose distance from the point of projection is

Two particles of charges +Q and -Q are projected from the same point with a velocity v in a region of uniform magnetic field B such that the velocity vector makes an angle $\theta$ with the magnetic field.Their masses are M and 2M, respectively.Then,they will meet again for the first time at a point whose distance from the point of projection is