Trigonometry help please..

Dj_Jestar · 15 Mar 2007 at 04:21

I have a vector. I know it's start point, the distance, and it's angle. How to I find out what the end point is on the grid?

e.g. the line starts at x: 23, y: 25, is 100 units long and the angle is 72 degrees.

It's been so long since I did anything more complicated than working out what change I'll get from a note, that I've completely forgotten

p.s. I'll also need to calculate fixed points along the line.. if that will make any difference?

Flanders · 15 Mar 2007 at 08:16

You can use sinθ = o/h for the first step. Where θ = 72° and h = 100.

The rest should be self explanatory.

Hope that helps

Dj_Jestar · 16 Mar 2007 at 00:25

Efour · 16 Mar 2007 at 02:23

its missile velocity x Flight time = Max range.

oh sorry....

Jonny ///M · 16 Mar 2007 at 02:48

Efour2 said:
its missile velocity x Flight time = Max range.

oh sorry....

You forgot the time it takes for the missile to accelerate to its max speed.

Shame on you.

Rebelius · 16 Mar 2007 at 02:53

Jonny ///M said:
You forgot the time it takes for the missile to accelerate to its max speed.

Shame on you.

projectiles don't accelerate horizontally.

Jonny ///M · 16 Mar 2007 at 02:57

Rebelius said:
projectiles don't accelerate horizontally.

Well its velocity.....ah **** knows it still has to accelerate....against the force of jesus.

Too much thinking....im going to bed.

Once i finish my cheerios

Rebelius · 16 Mar 2007 at 03:00

Jonny ///M said:
Well its velocity.....ah **** knows it still has to accelerate....against the force of jesus.

Too much thinking....im going to bed.

Once i finish my cheerios

they accelerate vertically due to mavity, but if you neglect frictional forces, there's no forces acting horizontally once it's in the air.

Jonny ///M · 16 Mar 2007 at 03:06

Rebelius said:
they accelerate vertically due to mavity, but if you neglect frictional forces, there's no forces acting horizontally once it's in the air.

How can it accelerat with mavity? mavity is pulling it down.....after it hits the peak of the curve thing...im :confused:

....bed

Nash · 16 Mar 2007 at 04:24

What do you mean by accelerate? Isn't an acceleration a change in velocity. If it's not moving then it lifts off it'll accelerate both upwards and horizontally as it gets faster and faster (assuming it's not going perfectly at right angles to the Earth)?