A 150-kg running back runs at 7 m/s into a stationary linebacker. It takes 0.9 s for the running back to be completely stopped. Find the magnitude of force exerted on the running back during the collision.

30 points - when can a theory be modified if a new type of technology allows for new observations that raise new questions? a. immediately, while the questions about the theory are being asked b. after new hypotheses related to the theory are tested in experiments c. only after the new observations disprove all parts of the theory d. while scientists begin to think about how the theory could improve

In what direction does an applied force move an object

Ne way in which elements differ from each other is the structure of the electron cloud in each element's atoms. in an electron cloud, an electron that is farther away from the nucleus has