Breaking the Sound Barrier: Calculating Time and Thrust of a Rocket Launch

Click For Summary

Homework Help Overview

The discussion revolves around a physics problem involving a rocket launch, focusing on calculating the time it takes to reach the sound barrier and the thrust required. The subject area includes dynamics and forces acting on the rocket and an instrument inside it.

Discussion Character

  • Mixed

Approaches and Questions Raised

  • Participants suggest starting with a free body diagram to analyze the forces acting on the instrument inside the rocket. There is an emphasis on understanding the relationship between tension, weight, and acceleration.

Discussion Status

The discussion is ongoing, with some participants seeking clarification on initial steps while others are attempting to guide them through the problem-solving process. There is no explicit consensus on the approach yet.

Contextual Notes

Some posts indicate confusion about how to proceed with the problem, and there are multiple instances of similar problems being presented, which may lead to potential misunderstandings in the discussion.

DKphysics
Messages
2
Reaction score
0
A 25,000-kg rocket blasts off vertically from the Earth's surface with a constant acceleration. During the motion considered in the problem, assume that g remains constant. Inside the rocket, a 15.0-N instrument hangs from a wire that can support a maximum tension of 35.0 N.

a) Find the minimum time for this rocket to reach the sound barrier (330 m/s) without breaking the inside wire and the maximum vertical thrust of the rocket engines under these conditions.

b) How far is the rocket above the Earth's surface when it breaks the sound barrier?


I have no idea where to start with this problem. The answers in the back of the book are:
(a) 25.3 seconds; 5.72 x 10^5 N/s
(b) 4170 m
 
Physics news on Phys.org
Start by drawing a free body diagram of the weight hanging inside the rocket.
 
hage567 said:
Start by drawing a free body diagram of the weight hanging inside the rocket.

Okay
 
So once you have that, what do you think you can do next?
 
A 2.49e4 kg rocket blasts off vertically from the Earth's surface with a constant acceleration. During the motion considered in the problem, assume that g remains constant. Inside the rocket, a 12.4 N instrument hangs from a wire that can support a maximum tension of 36.0 N.

a) Find the minimum time for this rocket to reach the sound barrier (330 m/s) without breaking the inside wire and the maximum vertical thrust of the rocket engines under these conditions.

b) How far is the rocket above the Earth's surface when it breaks the sound barrier?

I have no idea what to do.
 
Go to Post #2. Follow steps there.

(It's better not to add new problems to old posts.)
 
Are you mocking the other guy by making a name similar to his? I find this either very coincidental, or pretty hilarious...
 

Similar threads

  • · Replies 7 ·
Replies
7
Views
3K
  • · Replies 42 ·
2
Replies
42
Views
6K
Replies
3
Views
5K
  • · Replies 13 ·
Replies
13
Views
2K
  • · Replies 9 ·
Replies
9
Views
2K
Replies
1
Views
2K
  • · Replies 22 ·
Replies
22
Views
3K
  • · Replies 12 ·
Replies
12
Views
2K
  • · Replies 3 ·
Replies
3
Views
3K
  • · Replies 5 ·
Replies
5
Views
2K