Is it possible for the acrobat to rebound to a height greater than her initial height? explain. (select all that apply.) yes. the acrobat can provide mechanical energy by pushing herself up while in contact with the springboard. no. there is no external source of energy to provide the potential energy at a greater height. yes. the acrobat can bend her knees while falling and then straighten them as if jumping when bouncing upward again. yes. elastic energy is always present in the spring and can give the acrobat greater height than initially. no. the kinetic energy that the acrobat gains on the way down is converted entirely back into potential energy when she reaches the initial height.

In this experiment, you will use a track, a toy car, and some washers to explore newton’s first two laws of motion. you will make observations and collect data regarding the motion of these objects. in the space below, write a general scientific question that you will answer by doing this experiment.

Identify the type of synthetic material used in each object

Askydiver weighing 140 lb (including equipment) falls vertically downward from an altitude of 19,000 ft and opens the parachute after 18 s of free fall. assume that the force of air resistance, which is directed opposite to the velocity, is of magnitude 0.55|v| when the parachute is closed and is of magnitude 14|v| when the parachute is open, where the velocity v is measured in ft/s. assume that acceleration due to gravity has magnitude 32 ft/s/s; remember that weight is the product of mass and gravitational acceleration. (a) find the speed of the skydiver when the parachute opens. (b) find the distance fallen before the parachute opens. (c) what is the limiting velocity vl after the parachute opens? (d) determine how long the sky diver is in the air after the parachute opens. (e) plot the graph of velocity versus time from the beginning of the fall until the skydiver reaches the ground.