Front side air. A skateboarder is practicing on the ???half-pipe??? shown in Figure P6.39, using a special friction less skateboard. (You can also ignore the kinetic energy of the skateboard???s wheels.)?

(a) If she starts from rest at the top of the half-pipe, what is her speed at the bottom??

(b) If the skateboarder has mass m = 55 kg, what is her apparent weight at the bottom of the half-pipe??

(c) What speed does she then have when she reaches the top edge on the other side of the half-pipe??

(d) Now suppose she has a speed of 11 m/s at the bottom of the half pipe. What is the highest point she can reach?

Figure P6.39

?

4.0 m