Electric field direction is defined as the force direction on what sign of test charge?

State the relation between electric force and electric field for a charge \(q\).

A negative charge is placed in an electric field pointing east. Which way is the electric force on it?

A \(+2.0\,\mathrm{nC}\) charge experiences a \(6.0\times10^{-6}\,\mathrm{N}\) force north. Find the electric field magnitude and direction.

A charge \(-3.0\,\mu\mathrm{C}\) is placed in a uniform field \(800\,\mathrm{N\,C^{-1}}\) upward. Find the electric force.

A particle with charge \(+4.0\,\mu\mathrm{C}\) and mass \(2.0\times10^{-6}\,\mathrm{kg}\) is in a \(300\,\mathrm{N\,C^{-1}}\) field. Find its acceleration magnitude.

A charged particle of mass \(m\) and charge \(q<0\) starts from rest in a uniform electric field \(\vec E=E\hat\imath\). Write \(\vec a\) and describe the motion direction.

A \(+5.0\,\mathrm{nC}\) test charge experiences forces \(12\,\mu\mathrm{N}\) right and \(9\,\mu\mathrm{N}\) up from different sources. Find the net electric field vector at the point.

A particle of known mass \(m\) enters a uniform electric field with horizontal speed \(v_0\), and the field is vertical. Derive the vertical deflection after it travels horizontal distance \(L\), keeping the sign of \(q\).

Two particles with charges \(q_1\) and \(q_2\) but the same mass are released from rest in the same uniform electric field. Derive the condition under which they have equal acceleration vectors, and distinguish equal magnitude from equal vector acceleration.