Question

Consider the skateboarder in the figure below. If she has a mass of 53 kg, an Inltial velocity of 25 m/s, and a velocity of 13 m/s at the top of the ramp, what is the work done by friction on the skateboarder? Ignore the kinetic energy of the skateboard's wheels. 5.0 m to

Answer 1

mass of skateboarder= 53 kg

initial velocity = 25 m/s

velocity at top of ramp = 13 m/s

height of ramp = 5 m

initial kinetic energy of skate boarder = 0.5*53*25²=16562.5 J

initial potential energy of skateboarder = 0

initial total energy = 16562.5+0=16562.5 J

final kinetic energy of skateboarder = 0.5*53*13²=4478.5 J

final potential energy of skateboarder= 53*9.8*5=2597 J

Final total energy = 4478.5+2597=7075.5 J
energy lost to friction = 16562.5-7075.5=9487 J

Work done by friction = 9487 J