ATAR Notes: Forum

VCE Stuff => VCE Mathematics => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Specialist Mathematics => Topic started by: azn_dj on October 11, 2011, 11:04:15 am

Title: Projectile Motion?
Post by: azn_dj on October 11, 2011, 11:04:15 am

Hey how do you derive the equations for projectile motion in vector form?
Thanks, all :)

Title: Re: Projectile Motion?
Post by: tazza on October 12, 2011, 01:44:28 pm

Start off with acc(t) = -9.8j, and then go from there (anti deriving to get velocity and position, whilst using initial conditions.

Title: Re: Projectile Motion?
Post by: costa94 on October 12, 2011, 07:04:48 pm

a = -gj
v = -gtj + v(0)
r = -1/2gt^2j + v(0)t + r(0)

Title: Re: Projectile Motion?
Post by: azn_dj on October 15, 2011, 11:04:32 am

I understand in the J direction, but what about the i direction?

Title: Re: Projectile Motion?
Post by: azn_dj on October 15, 2011, 11:05:31 am

Oh wait hang on a second, I think I have answered my own question
V(0) will be xcos(theta) i + x sin(theta) j
Thanks anyways :)

Title: Re: Projectile Motion?
Post by: costa94 on October 15, 2011, 11:20:19 am

i velocity is always constant unless there is air resistance, but spec rarely says that otherwise it tells you 'resistance blergh' (not in projectile motion though...)
j comp. is just affected by gravity

Title: Re: Projectile Motion?
Post by: azn_dj on October 15, 2011, 09:45:32 pm

Just had to jog my memory, that's all. Thanks everyone :)