Force provided during deceleration?

AI Thread Summary
The discussion revolves around calculating the force exerted by rockets on a spacecraft decelerating from 8 m/s to 0.03 m/s over 10 seconds while burning 100 kg of fuel. The user attempts to determine acceleration using the formula ∆v/t and then applies F = m x a to find the force. However, the situation involves a variable mass due to fuel consumption, complicating the calculations. The user expresses confusion regarding momentum changes and the correct application of equations. Clarification on handling variable mass scenarios in force calculations is needed.
TommyChestnut
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Homework Statement


A spacecraft with a mass of 9100kg (incl fuel) traveling at 8 m/s
Rockets fire for 10 seconds burning 100kg of fuel slowing the spacecraft to 0.03 m/s
What is the force the rockets provided during the 10 seconds?

Homework Equations


acceleration = ∆v/t
F = m x a[/B]

The Attempt at a Solution


a = 8m/s - 0.03m/s = 7.97m/s
F = 9100kg x 7.97ms / 10s
F = 7.252.7

I just wanted to check the equations I have used for this problem are correct as I am getting confused with changes in momentum F x t = m x v[/B]
 
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TommyChestnut said:

Homework Statement


A spacecraft with a mass of 9100kg (incl fuel) traveling at 8 m/s
Rockets fire for 10 seconds burning 100kg of fuel slowing the spacecraft to 0.03 m/s
What is the force the rockets provided during the 10 seconds?

Homework Equations


acceleration = ∆v/t
F = m x a[/B]

The Attempt at a Solution


a = 8m/s - 0.03m/s = 7.97m/s
F = 9100kg x 7.97ms / 10s
F = 7.252.7

I just wanted to check the equations I have used for this problem are correct as I am getting confused with changes in momentum F x t = m x v[/B]
You have a variable mass situation here, since you are burning fuel to slow the spacecraft .
 

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