Calculate the magnitude of the electric force between two charged balloons if one of the
balloons has a charge of 15 * 10 ^ - 8 C and the
other balloon has a charge of 7*10 ^ - 7 107C.
Their centers are located exactly .5 meters apart

The rigid beam is supported by the three suspender bars. bars ab and ef are made of aluminum and bar cd is made of steel. if each bar has a cross-sectional area of 450 mm2, determine the maximum value of p if the allowable stress is (σallow)st = 200 mpa for the steel and ( σallow)al = 150 mpa for the aluminum. est = 200 gpa and eal = 70 gpa.