Moving Charges ...

Identify in which of the following cases would the charge experience a magnetic force?
I. The stationary charge is placed inside the magnetic field 
II. The charge is moving and its velocity is perpendicular to the magnetic field lines
III. The charge is moving and its velocity is parallel to the magnetic field lines

A charged particle is moving in circular path of radius 100 meters in a uniform magnetic field. If mass of the charged particle is $$9.1$$ x $$10^{-31}$$ kg and its speed is 3 x $$10^7$$ m/s. Which of the following is the best estimate of the order of magnitude of the magnetic force needed to maintain this orbit?

An electron moving with velocity 'v' enters a magnetic field as shown in the above figure.
Identify in which direction, the electron will experience a force ?

A particle of mass m is moving in a circular path in a uniform magnetic field as shown above. What is the sign of charge on the particle?

A proton of charge $$e$$ moving at speed $$v_0$$ is placed midway between two parallel wires a distance $$a$$ apart, each carrying current $$I$$ in opposite directions.
The force on the proton is:

A proton of charge $$'e'$$ moving at speed $$'v_0\ '$$ is placed midway between two parallel wires $$a$$ distance a apart, each carrying current $$I$$ in the same direction.
The force on the proton is 

A proton of charge $$e$$ moving at speed $$v_0$$ is placed midway between two parallel wires $$a$$ distance a apart, each carrying current $$I$$ in the same direction.
The force on the proton is:

A proton of charge $$e$$ and mass $$m_p$$ moves in a circular path of radius $$r$$ in a uniform magnetic field $$B$$.
The momentum of the proton can be described by the expression:

Two wires are pictured below, both carrying current toward the east. What is the direction of the force exerted by wire 2 on wire 1?

The diagram above shows a negatively charged ball moving to the right below a wire carrying conventional current to the right. Both are in the plane of the screen.
What is the direction of the force on the negatively charged ball at the place it is pictured?