If a weight lifter holds a 200 kg barbell in place over his head, he a: does no work because the force he applies does not cause the barbell to move. b: does work because the barbell is heavy to hold.

Alow cost, low earth orbit (leo) satellite is to be fabricated at a university, for subsequent launch by rocket. what are the constraints and objectives for selection of a material suitable for the satellite bus (i.e. the structure)? explain each in brief. (15 marks) b)suggest sources of data which could support the selection of materials for applications in space. (5 marks) c) set weights for the objectives listed in (2a) using the digital logic method. (5 marks)

The of a machine determines its "usefulness." a. input force b. output force c. mechanical advantage

The buildup of charges on an object is called