Newton's Laws of Motion on a rocket

Click For Summary

Homework Help Overview

The discussion revolves around the application of Newton's Laws of Motion in the context of a rocket landing vertically on Earth. The original poster presents a scenario involving an 8.00-kg instrument suspended by a wire inside the rocket, which is decelerating at a rate of 2.50 m/s².

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning, Assumption checking

Approaches and Questions Raised

  • Participants discuss the forces acting on the instrument, including gravitational force and tension in the wire. There are inquiries about the free-body diagram and the correct application of Newton's second law to find the tension force.

Discussion Status

Some participants have provided insights into the forces involved and questioned the original poster's calculations regarding tension. There is an exploration of the relationship between the rocket's deceleration and the forces acting on the instrument, indicating a productive dialogue on the topic.

Contextual Notes

Participants are navigating the complexities of the problem, including the effects of the rocket's acceleration on the forces acting on the instrument. There is a mention of potential misunderstandings regarding the direction of forces and the resulting calculations.

plshelpme
Messages
3
Reaction score
0
Suppose the rocket is coming in for a vertical landing at the surface of the earth. The captain adjusts the engine thrust so that rocket slows down at the rate of 2.50m/s^2 . A 8.00-kg instrument is hanging by a vertical wire inside a space ship.

1]Draw a free-body diagram for the instrument.

2]Find the force that the wire exerts on the instrument.
 
Physics news on Phys.org
Welcome to PF.

I wonder why you didn't use the template that is provided when you make a new post... anyway, what did you come up with?
What does your free body diagram look like? Which forces are acting on the block, in what directions and possibly magnitudes?
 
CompuChip said:
Welcome to PF.

I wonder why you didn't use the template that is provided when you make a new post... anyway, what did you come up with?
What does your free body diagram look like? Which forces are acting on the block, in what directions and possibly magnitudes?

w=mg acting on the instrument downwards. tension acting upwards. with a downward accelerating force.

my attempted ans for qn 2 is mg - T = 2.5 * 8. gives the wrong tension result...

can enlight me on where the mistake lies?
 
If the rocket is slowing, then the acceleration of the rocket is 2.5 upwards. This means that the Tension will be mg+2.5m = T = m*(g + 2.5)

Even though the ship has downward velocity - in the direction of gravity - I read it that the speed is slowing at 2.5, hence this will create a force (m*a) in addition to gravity that will add to the force of gravity in the tension on the instrument won't it?
 

Similar threads

  • · Replies 42 ·
2
Replies
42
Views
6K
  • · Replies 32 ·
2
Replies
32
Views
6K
  • · Replies 7 ·
Replies
7
Views
3K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 13 ·
Replies
13
Views
2K
  • · Replies 3 ·
Replies
3
Views
3K
Replies
3
Views
5K
Replies
3
Views
2K
Replies
6
Views
9K
  • · Replies 9 ·
Replies
9
Views
2K