The backwards (friction) force on the athlete is 42 N, the forwards force of the wind is 21 N, and the force from her muscles is 84 N. Calculate the resultant force on the runner. Give its direction.

What do butterflies have on their feet which allows them to sense different strengths and types of nectar? a.mechanoreceptors b.acoustic receptors c.substratum receptors d.chemoreceptors

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.

You can watch static electricity in action by rubbing an inflated balloon against your hair. your hair will actually stand on its end! it does this because each hair becomes charged, and they all repel one another.