A square insulating sheet whose sides have length L is held horizontally. The sheet has a charge of Q spread uniformly over its area. Part A

Calculate the electric field at a point located a distance r1 above the center of the sheet. Use the appropriate approximations based on the fact that r1 ? L.

Take the permittivity of free space to be ?0.

Part B

Estimate the electric field at a point located a distance r2 above the center of the sheet. Use the appropriate approximations based on the fact that r2 ? L.

Astudent throws a water balloon with speed v0 from a height h = 1.76 m at an angle θ = 21° above the horizontal toward a target on the ground. the target is located a horizontal distance d = 9.5 m from the student’s feet. assume that the balloon moves without air resistance. use a cartesian coordinate system with the origin at the balloon's initial position. (a) what is the position vector, rtarge t, that originates from the balloon's original position and terminates at the target? put this in terms of h and d, and represent it as a vector using i and j. (b) in terms of the variables in the problem, determine the time, t, after the launch it takes the balloon to reach the target. your answer should not include h. (c) create an expression for the balloon's vertical position as a function of time, y(t), in terms of t, vo, g, and θ. (d) determine the magnitude of the balloon's initial velocity, v0, in meters per second, by eliminating t from the previous two expressions.

In which type of system is power held solely by the central government and not shared with regional governments? group of answer choices federal unitary confederate oligarchic

Sawyer is studying diffraction. he draws a diagram of a plane wave to show how light waves travel. which best describes sawyer’s error? the wave fronts should be perpendicular to the direction in which the waves move. the arrow showing the direction of movement of the waves should be pointing to the left. the arrow showing the direction of movement of the waves should be pointing downward. the wave fronts should be both parallel and perpendicular to the direction in which the waves move.