- #1
aeb2335
- 26
- 0
This question of 2wd vs 4wd in a drag race has bugged me for a bit and I was wondering if my conclusion makes scene. Most of the time that I can remember a 2wd will win over a similar 4wd car and I wanted some mathematical proof on why that is. I am not entirely sure where to begin this one...
Given:
(gross assumptions)
Both cars have the same mass, same moment of inertia for all four wheels, same wheel radius, both cars produce the same amount of power and torque. Both undergo rolling without slipping (just for simplicity) and assume that the coefficients of friction and rolling resistance is the same for all four wheels and between cars.
Find:
In a drag race over a set distance what car would achieve the highest velocity the fastest
Analysis: well I am kind of lost right now...but in essence my thinking is this...
sumtorques=Ia
2wd: T/2=Ia
4wd: T/4=Ia
So a 2wd car's wheels (and thus acceleration as atan*r) at a given power will be 2x that of a 4wd car...i feel like something is missing i made a free body diagram etc. but because the mu kenetic is the same on all four wheels and between cars the total loss for both cars is the same...help?
Given:
(gross assumptions)
Both cars have the same mass, same moment of inertia for all four wheels, same wheel radius, both cars produce the same amount of power and torque. Both undergo rolling without slipping (just for simplicity) and assume that the coefficients of friction and rolling resistance is the same for all four wheels and between cars.
Find:
In a drag race over a set distance what car would achieve the highest velocity the fastest
Analysis: well I am kind of lost right now...but in essence my thinking is this...
sumtorques=Ia
2wd: T/2=Ia
4wd: T/4=Ia
So a 2wd car's wheels (and thus acceleration as atan*r) at a given power will be 2x that of a 4wd car...i feel like something is missing i made a free body diagram etc. but because the mu kenetic is the same on all four wheels and between cars the total loss for both cars is the same...help?