Determine the velocity of the car after it has been floored for 8 seconds

AI Thread Summary
To determine the velocity of a car after 8 seconds of acceleration, the mass is 1200 kg, and the engine exerts a constant force of 9600 N while facing a drag force represented by D=160v. The equation of motion is m(dv/dt) = 9600 - 160v, which can be rearranged for integration. By substituting u=60-v, the left side can be integrated, leading to a solution for velocity over time. Understanding the integration process is crucial for solving the problem accurately.
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Hey if anyone could please tell me how to do this it would be a great help.

ok the question asks about an accelerating car. The mass of the car is 1200kg. When the engine is floored it creates a constant forward force of 9600N. The drag created by the car is equal to this equation: D=160v. Determine the velocity of the car after it has been floored for 8 seconds.
 
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You just need to solve the equation of motion:

m\frac {dv}{dt} = 9600 - 160 v

Just remember to keep your units consistent!
 
actually i am not familiar with that equation. and my calculus is poor. So if anyone could explain this further, thanks!
 
1200\frac {dv}{dt} = 9600 - 160 v= 160(60- v)
is the same as
\frac{dv}{60-v}= \frac{160}{1200}dt= \frac{1}{20}dt

To integrate the left side, let u= 60- v so that du= -dv and the equation becomes
-\frac{du}{u}= \frac{1}{20}dt

You ought to be able to integrate that.
 
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