Suppose a soccer ball is kicked from the ground at an angle 20.0º above the horizontal at 8.00 m/s. The initial y-velocity is determined to be 2.74 m/s. If the ball lands at the same height at which it was kicked, what is the value of Δy for the ball?

Four point charges each having charge q are located at the corners of a square having sides of length a. find symbolic expressions for the following. (a) the total electric potential at the center of the square due to the four charges (use any variable or symbol stated above along with the following as necessary: ke.) vtotal= (b) the work required to bring a fifth charge p from infinity to the center of the square (use any variable or symbol stated above along with the following as necessary: w=