Forces and kinetic energy problem

AI Thread Summary
Shawn's bike and rider have a combined mass of 43.5 kg, and he travels 1.3 km in 10.4 minutes at a constant velocity. The average velocity is calculated to be approximately 2.08 m/s after converting units. The kinetic energy formula, KE = 1/2 mv^2, is identified as the method to solve for kinetic energy. The expected answer for Shawn's kinetic energy is 94.4014 J. The discussion highlights the importance of understanding kinetic energy in solving physics problems.
kza62
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1. Homework Statement
Shawn and his bike have a total mass of 43.5 kg. Shawn rides his bike 1.3 km in 10.4 min at a constant velocity.
The acceleration of gravity is 9.8 m/s^2
What is Shawn's kinetic energy?


2. Homework Equations
F = ma
Ff = u * Fn
Fn = mg
avgV = x/t
x = 1/2(Vf + Vi)t


3. The Attempt at a Solution

ok so I converted km to m and min to s:
x = 1300m
t = 624s
and then i used avgV = x/t so avgV = ~2.08333 m/s

i have no idea what kinetic energy is, this hasn't been covered in class yet but I wanted to get ahead because I think I am coming down with the flu. The answer to the problem is supposed to be 94.4014 J but I have no idea how to set this problem up to get this. Please help me! Thanks.
 
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oooo ok so KE = 1/2mv^2
alright now i can finish this
thanks!
 

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