An object whose mass is 100 lb falls freely under the influence of gravity from an initial elevation of 600 ft above the surface of earth. the initial velocity is downward with a magnitude of50 ft/s. the effect of air resistance is negligible. determine the velocity, in ft/s, of the object just before it strikes earth. assumeg= 31.5 ft/s2

The movement of electrons between atoms is called an

Which of the following forces require physical contact? tension air resistance friction magnetic force applied force

To place a communications satellite into a geosynchronous orbit at an altitude of 22,240 mi above the surface of the earth, the satellite first is released from a space shuttle , which is in a circular orbit at an altitude of 185 mi, and then is propelled by an upper-stage booster to its final altitude. as the satellite passes through a, the booster's motor is fired to insert the satellite into an elliptic transfer orbit. the booster is again fired at b to insert the satellite into a geosynchronous orbit. knowing that the second firing increases the speed of the satellite by 4810ft/s, determine (a.) the speed of the satellite as it approaches b on the elliptic transfer orbit, (b.) the increase in speed resulting from the first firing at a.