1. A rocket traveling at 400 m/s fires its booster rockets until the craft reaches 550 m/s. If the boosters fire for 30 seconds, what was the acceleration of the rocket?

The answer is 4f======since electrostatic force is given by    we let f be the electrostatic force when  r = 1 m    if we let  denote the electrostatic force when the distance is decreased so that r = 0.5m, then    we established earlier that f = kq₁q₂. therefore    the force will now be 4f.