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CmbkG
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Homework Statement
A projectile of mass m is fired from the ground with a speed of 200m/s at an angle to the ground of 30 degrees. Assuming that the air resistance is linear, given by -mλv where v is the projectile's velocity and λ=0.1 s^-1, then find (taking g=10m.s^-2)
(a)the time of flight (time till it hits the ground again)
(b)the horizontal distance travelled
(c)the maximum height reached during the motion
Homework Equations
The Attempt at a Solution
Vx = Vo cosα
Vy = Vo sinα - gt
X = Xo + Vocosαt
Y = Yo + V0sinαt - gt^2/2
Suppose the particle is launched from the origin:
Xo=Yo=0
therefore: X = Vo cos αt
Y = Vo sinαt - gt^2/2
Eliminating t: t=X/VoCosα
Substitute into Y: Y=Tanαx - gX^2/2VO^2(Cosα)^2
Hence: 0=Tan(30X) - 10X^2/2(200)^2(Cos(30))^2
=Tan(30X) - 10X^2/60000