bennyd2012
New member
- Joined
- Feb 8, 2012
- Messages
- 4
integration
Could anyone help me with the following question.... i am very confused :???:
A rocket is modelled by a particle that moves along a vertical line. From launch, the rocket rises until its motor cuts out after 17seconds. At this time it has reached a height of 580metres above the launch pad and attained an upward velocity of 120ms^-1. From this time on, the rocket has constant upward acceleration -10ms^-2(due to the affect of gravity alone).
Choose the s-axis (for the position of the particle that represents the rocket) to point upwards, with origin at the launch pad. Take t=0 to be the time when the rocket motor cuts out.
A. What is the maximum height (above the launch pad) reached by the rocket?
b. How long from launch does the rocket take to reach the mamium height?
C. After how long (from launch) does the rocket crash onto the launchpad? give your answer in seconds correct to one decimal place?
Ok so for A. i am using v^2-2as=v0^2-2a(so)
vo=25 a =-10 does v and so = 0??? so my height was 31.25 which makes no sense since height in question is 580 any other suggestions for a?
Could anyone help me with the following question.... i am very confused :???:
A rocket is modelled by a particle that moves along a vertical line. From launch, the rocket rises until its motor cuts out after 17seconds. At this time it has reached a height of 580metres above the launch pad and attained an upward velocity of 120ms^-1. From this time on, the rocket has constant upward acceleration -10ms^-2(due to the affect of gravity alone).
Choose the s-axis (for the position of the particle that represents the rocket) to point upwards, with origin at the launch pad. Take t=0 to be the time when the rocket motor cuts out.
A. What is the maximum height (above the launch pad) reached by the rocket?
b. How long from launch does the rocket take to reach the mamium height?
C. After how long (from launch) does the rocket crash onto the launchpad? give your answer in seconds correct to one decimal place?
Ok so for A. i am using v^2-2as=v0^2-2a(so)
vo=25 a =-10 does v and so = 0??? so my height was 31.25 which makes no sense since height in question is 580 any other suggestions for a?