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terwilld
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Homework Statement
This is not a homework question per se but rather something I was thinking about while driving the other day.
I am in a car on a hill with constant slope traveling at an initial speed. How can I come up with a set of equations describing both velocity as a function of time and and height as a function of time.
Homework Equations
Ke = (1/2)MV^2
d(Ke)dt = -m*g*sin(slope)v
The Attempt at a Solution
All attempts to find solutions to this question have been fruitless. Most physics / calc books seem to offer this question in a simplified version: how far up the hill does the car make it. I am far more interested in plotting the curve of speed as a function of time.
Based on my understanding:
As the car travels up the hill, kinetic energy (Ke) is converted to potential energy: Ke = Pe. Potential energy = mgh. The kink seems to be that the change in potential energy is not the same. At the start, speed is the greatest, thus the change in potential energy is greatest ( = mg(sin(slope)*v). However as the car climbs the hill, its speed changes, thus the rate at which its speed changes, changes.
so far:
Initial conditions:
Keo = (.5)*mvo2.
dKe/dt = -mgsin(∅)vo
how can I relate these to t, take a derivative of the first equation and set it equal to the 2nd?