Register to reply

Bolt falls off rocket, find rocket acceleration

by stangeroo
Tags: acceleration, bolt, falls, rocket
Share this thread:
stangeroo
#1
Apr10-05, 05:36 PM
P: 13
A rocket is launched straight up with constant acceleration. Four seconds after liftoff, a bolt falls off the side of the rocket. The bolt hits the ground 6.70 s later.

Find the rockets acceleration.

I dont understand how to set up this problem, ive never done something like this , asked some friends and they didnt know how to do it. Any help would be greatly appreciated
Phys.Org News Partner Science news on Phys.org
World's largest solar boat on Greek prehistoric mission
Google searches hold key to future market crashes
Mineral magic? Common mineral capable of making and breaking bonds
Jameson
#2
Apr10-05, 06:13 PM
P: 788
Work backwards kind of. If it took 6.7 for the bolt to hit the ground, how high was it?

[tex]d = v_{i}t + \frac{1}{2}at^2[/tex]

vi = 0
a = -32 ft\sec^2 or -9.8 m\sec^2
t = 6.7 s

Solve for d.

Now, use the same equation and solve for "a" of the rocket.

[tex]d = v_{i}t + \frac{1}{2}at^2[/tex]

d = part a
vi = 0
t = 4


Jameson
Doc Al
#3
Apr10-05, 08:10 PM
Mentor
Doc Al's Avatar
P: 41,316
Do it in two parts, but like this:
Part 1: Find the height and speed of the rocket after 4 seconds in terms of the rocket acceleration. Use:
[itex]h = 1/2 a t^2[/itex] and
[itex]v = a t[/itex]

Part 2: Realize that the initial height and speed of the bolt equals the height and speed of the rocket after 4 seconds (which was calculated in part 1). The height of the bolt after it leaves the rocket is:
[itex]h = h_0 + v_0t -(g/2)t^2[/itex],
using [itex]h_0[/itex] and [itex]v_0[/itex] (in terms of a) from part 1; set h = 0 when t = 6.7 seconds. Solve for a.

stangeroo
#4
Apr10-05, 11:19 PM
P: 13
Bolt falls off rocket, find rocket acceleration

thank you guys


Register to reply

Related Discussions
The Multiple Launch Rocket System and Rocket Noises General Physics 1
The acceleration of a rocket General Physics 18
Rocket Acceleration Introductory Physics Homework 1
Acceleration of rocket? Introductory Physics Homework 2
Acceleration on Rocket Classical Physics 3