魅影直播

(I) Determine the magnitude and direction of the electric field 21.7 cm directly above an isolated charge\({\bf{33}}{\bf{.0}} \times {\bf{1}}{{\bf{0}}^{{\bf{ - 6}}}}{\bf{ C}}\).

(I) A downward electric force of 6.4 N is exerted on a\( - {\bf{7}}{\bf{.3}}{\rm{ }}\mu {\bf{C}}\)charge. Find the magnitude and direction of the electric field at the position of this charge.

(II) Determine the magnitude of the acceleration experienced by an electron in an electric field of\({\bf{756 N/C}}\).How does the direction of the acceleration depend on the direction of the field at that point?

(II) Determine the magnitude and direction of the electric field at a point midway between a \( - {\bf{8}}{\bf{.0}}{\rm{ }}\mu {\bf{C}}\) and a\( + 5.8{\rm{ }}\mu {\bf{C}}\)charge 6.0 cm apart. Assume no other charges are nearby.

(II) Draw, approximately, the electric field lines about two point charges, +Q and 鈥�3Q, which are a distance l apart.

(II) What is the electric field strength at a point in space where a proton experiences an acceleration of 2.4 million 鈥�g鈥檚鈥�?

(II) An electron is released from rest in a uniform electric field and accelerates to the north at a rate of\({\bf{105 m/}}{{\bf{s}}^{\bf{2}}}\).Find the magnitude and direction of the electric field.

(II) The electric field midway between two equal but opposite point charges is\({\bf{386 N/C}}\)and the distance between the charges is 16.0 cm. What is the magnitude of the charge on each?

(II) Calculate the electric field at one corner of a square 1.22 m on a side if the other three corners are occupied by \({\bf{3}}{\bf{.25 \times 1}}{{\bf{0}}^{{\bf{ - 6}}}}\;{\bf{C}}\) charges.

(II) Calculate the electric field at the center of a square 42.5 cm on a side if one corner is occupied by a \({\bf{ - 38}}{\bf{.6}}\;{\bf{\mu C}}\) charge and the other three are occupied by \({\bf{ - 27}}{\bf{.0}}\;{\bf{\mu C}}\) charges.