4) Two objects, A with mass of 3.0 kg and object B with mass of 1.0 kg, move on a frictionless horizontal surface. Object A moves to the right at a constant velocity of 5.0 m/s, while object B moves to the left at a constant velocity of -2.0 m/s. They collide and bounce off one another (a perfectly elastic collision). Object A is now moving to the left at -2.0 m/s,

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.

What would be the strength of earth's gravitational field at a point where an 80.0 kg astronaut would experience a 80% reduction in weight

Cathy is pedaling down a steep hill on her bicycle and wants to be able to coast up the next hill, which is 25 meters high, without pedaling. cathy and her bicycle have a mass of 75 kg. assuming her bicycle is 100% efficient, what would her speed have to be?