Moving Charges ...

A deutron of kinetic energy 50 keV is describing a circular orbit of radius 0.5 m, in a plane perpendicular to magnetic field $$\vec B$$. The kinetic energy of a proton that discribes a circular orbit of radius 0.5 m in the same plane with the same magnetic field $$\vec B$$ is

Ampere's circuital law holds good for:

A charge $$q=-4\mu C$$ has an instantaneous velocity $$\vec{v}=(2\hat{i} -3\hat{j}+\hat{k})\times {10}^{6}m/s$$ in a uniform magnetic field $$\vec{B}=(2\hat{i} +5\hat{j}-3\hat{k})\times {10}^{-2}T$$.What is the force on the charge?

An electron travelling with a speed u along the positive x-axis enters into a region of magnetic field where $$B = - B_0 \widehat k (x  > 0)$$. It comes out of the region with speed v then

A beam of electrons enters normally in a magnetic field. find the correct condition. 

An electron moving with uniform velocity in x direction enters a region of uniform magnetic field along y-direction. Which of the following physical quantity(ies) is (are) non zero and remain constant ? 
I. Velocity of the electron 
II. Magnitude of the momentum of the electron. 
III. Force On the electron. 
IV. The kinetic energy of electron. 

A closed curve encircles several conductors.The line integral $$\int{\vec{B}\cdot d\vec{l}}$$ around this curve is $$3.83\times {10}^{-7} T-m$$. What is the net current in the conductors?

What reading would you expect of a square-wave current, switching rapidly between $$+0.5A$$ and $$-0.5A$$, when passed through an ac ammeter?

If the acceleration and velocity of a charged particle moving in a constant magnetic region is given by $$\vec{a}={a}_{1}\hat{i}+{a}_{2}\hat{k},\vec{v}={b}-{1}\hat{i}+{b}_{2}\hat{k}$$.[$${a}_{1},{a}_{2},{b}_{1}$$ and $${b}_{2}$$ are constants],then choose the wrong statement

The figure shows the cross-section of two long coaxial tubes carrying equal currents $$I$$ in opposite directions. If $${B}_{1}$$ and $${B}_{2}$$ are magnetic fields at point 1 and 2, as shown in figure then