Three identical stars of mass m form an equilateral triangle that rotates around the triangle’s center as the stars move in a common circle about that center. the triangle has an edge length of l. what is the speed of the stars?

Which simple machine is not part of this compound machine? a. lever b. pulley c. inclined plane d. wheel and axle

An incident ray through the focal point of a spherical mirror will: reflect through the center of curvature. reflect back through the focal point. reflect parallel to the principle axis. reflect the same direction as the incident ray.

Asolid round steel rod 6.25 mm in diameter and 375 mm long is rigidly bonded to the end of solid square brass rod 25 mm on a side and 300 mm long. the geometric axes of the bare are along the same line. an axial tensile force of 5.4 kn is applied at the extreme ends of the assembly. for steel e = 200 gpa and for brass e = 90 gpa. determine the total elongation for the assembly.