Amass weighing 4 pounds is attached to a spring whose constant is 2 lb/ft. the medium offers a damping force that is numerically equal to the instantaneous velocity. the mass is initially released from a point 1 foot above the equilibrium position with a downward velocity of 6 ft/s. determine the time at which the mass passes through the equilibrium position. (use g = 32 ft/s2 for the acceleration due to gravity.)

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=