(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A car starts at 100 m/s and deploys a parachute. After 10 seconds its speed decreases to 45.45 m/s. Calculate the distance the car has travelled in this duration. The effects of ground resistance are ignored.

drag coefficient and planform area product (Cd * A) = 4 m^2

2. Relevant equations

drag force, Fd = 1/2 (rho) * u^2 * Cd * A

rho = density, 1.22 kg/m^3

u = speed

Cd = drag coefficient

A = planform area

-Fd = m du/dt

m = mass

3. The attempt at a solution

Basically I managed to calculate the speed after 10 seconds which is 45.45 m/s by integrating -Fd = m du/dt.

I cannot use the SUVAT equations to calculate the distance because it is not constant acceleration (I think). Besides, even if I try this method I get the question wrong. The answer from my lecturer is supposedly s=657m.

I think the above equation must be integrated again to get the displacement but I have tried and I think I'm missing something because I can't manipulate it so that I end up with s in the formula.

Please help as I have pulled my hair off trying to figure this out to no avail.

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# Homework Help: Effects of drag on the distance of a car travelling

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