This is probably a maths question which im struggling with(adsbygoogle = window.adsbygoogle || []).push({});

the question states that

drag is proportional to the square of the velocity

D = kv^2

And there is a linear relationship between the square of the velocity and the acceleration

dv/dt = - 0.0154 v^2 + 0.402827

assume the mass of the object is 700 kg

F = ma

F = 700 dv/dt

and the force = propulsion- drag = P - D

P - D = 700 dv/dt

dv/ dt = ( P - D) / 700

with this data below how do i find the drag and the propulsion

v^2 (m/s)__________( dv/dt) , ms/s/s

0.6241_____________0.39

5.0176_____________0.32

11.2225____________0.23

16.81______________0.15

20.7025____________0.09

23.2324____________0.05

I tried putting the linear equation in the Newton second law

dv/ dt = ( P - D) / 700

dv/dt = - 0.0154 v^2 + 0.402827

so , ( P - D) / 700 = - 0.0154 v^2 + 0.402827

but how do i find the P and D ?

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# Homework Help: Velocity and acceleration and drag

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