Moving Charges ...

The incorrect statement of the following is:

A proton and an alpha particle are separately projected in a region , where a uniform magnetic field exists. The initial velocities are perpendicular to the direction of magnetic field . If both the particles move along circles of equal radii , the ratio of momentum of proton to alpha particle( $$\dfrac{P_p}{P_a}$$)

If an electron of velocity $$(2\hat{i}+3\hat{j})$$ is subjected to magnetic field of $$4\hat{k}$$, then its:-
(a) path will change
(b) speed does not change
(c) path must be circular
(d) momentum is constant.

A charged particle moves in a uniform magnetic field perpendicular to it, with a radius of curvature 4 cm. On passing through a metallic sheet it looses  half of its kinetic energy, then the radius of curvature of the particle is :

The coil of a tangent galvanometer is put in the magnetic meridian

The charged particles traverse identical helical paths in a completely opposite sense in a uniform magnetic field $$B={ B }_{ 0 }\hat { k }$$.

A positively charged particle moving with constant speed due east enters a region of uniform magnetic field directed vertically upwards this particle will-

A charged particle of mass 1 $$\mu $$ g and charge 1 $$\mu $$ C having speed 2m/s moves in a magnetic field 1 $$\hat{K} $$ Tesla. At a certain instant its velocity is $$\bar{V}=\hat{i}+\hat{j}+m\hat{k} $$ . The value of 'm' is ________________.

A current carrying wire and a rectangular loop are placed as shown in figure then-

The magnetic field strength at a point P distant r due to an infinite straight wire as shown in the figure carrying i is :