View Full Version : A test rocket is launched by accelerating it along a200m incline at 1.25m/s2 starting
juju88jk
Feb 15, 2012, 12:37 PM
A test rocket is launched by accelerating it along a200m incline at 1.25m/s2 starting from rest at PointA. The incline rises 35 degrees above the horizontal, and at the instant the rocket leave it, its engines turn off and it issubject only to gravity (air resistance can be ignored). Find(a) the maximum height above the ground that the rocket reaches,and (b) the greatest horizontal range of the rocket beyond pointA.
ebaines
Feb 16, 2012, 08:54 AM
To do this you need to:
1. Find the vertical and horizontal components of the rocket's velocity when it leaves the track. Its velocity can be found from v^2 = 2ad. It's horizonal and vertical components are found by applying the appropriate sine and cosine values for 25 degrees.
2. The max height can be found from v_2^2 - v_1^2 = 2ad. Here v_2 = 0 (at max height the rocket is neither rising nor falling), v_1 is the initial vertical component of velocity, and a is -g. This gives you the height it rises above the ramp - you should add the height of the ramp to get the total altitude above the ground.
3. Find the time it takes to reach max altitude, then fall from that altitude. You can use v_2 = v_1-gt to calculate time to reach max altitude. Then add to that the time it takes to fall from max altitude, using h= 1/2 g t^2
4. Finally, the horizontal distance covered can be found from d = (v_h)t, where v_h is the rocket's horizontal velocity and t is the total time that you found in step 3.
Hope this helps. Post back and show us your work and we'll check it for you.